Easy Southern Yellow Squash Casserole: A Creamy, Cheesy Comfort Food Classic
There’s nothing quite like a classic Southern yellow squash casserole to bring comfort to your table. This simple, yet incredibly satisfying dish features tender slices of yellow squash, enveloped in a rich and creamy sauce, infused with the delightful tang of sour cream and a generous blend of melty cheddar and parmesan cheeses. Crowned with a golden, buttery Ritz cracker topping, it’s a side dish that promises a perfect balance of textures and flavors. Whether it’s a festive holiday gathering or a casual summer barbecue, this squash casserole effortlessly elevates any meal, offering a taste of homestyle goodness that everyone will adore. It’s an approachable recipe, making it ideal for both seasoned cooks and those new to the kitchen, delivering impressive results with minimal fuss.
Why This Recipe Works
This yellow squash casserole isn’t just a recipe; it’s a culinary triumph that consistently delivers on taste, texture, and ease. Its appeal lies in its straightforward approach to creating something truly delicious and comforting. First, the tender yellow squash provides a delicate sweetness that pairs beautifully with the savory, creamy base. We’re talking about perfectly cooked squash – not mushy, but soft enough to melt in your mouth, retaining just a hint of firmness. The secret to its luscious interior is the harmonious blend of sour cream, which adds a crucial tang and velvety smoothness, along with sharp cheddar and nutty Parmesan cheeses that contribute irresistible depth and a gooey, cheesy pull.
Beyond its incredible flavor profile, this casserole is a champion of versatility. It shines as a quintessential holiday side dish, standing proudly alongside a roasted turkey or glazed ham. Yet, it’s equally at home at a summer potluck or a casual weeknight dinner, proving its year-round relevance. The buttery Ritz cracker topping provides that satisfying crunch and a salty contrast that completes every bite. What truly makes this recipe a standout is its efficiency; it comes together in just about 30 minutes of active preparation time, making it an excellent option when you need a crowd-pleasing dish without spending hours in the kitchen. Simple, satisfying, and undeniably comforting – this is a recipe you’ll return to again and again.
In my opinion, squash in all its wonderful varieties is often highly underrated. While many gravitate towards more common vegetable sides, the humble squash offers incredible versatility and flavor. From savory zucchini casserole to the earthy goodness of baked spaghetti squash, and even the sweet and savory delight of air fryer acorn squash slices, these are some of the best side dishes that simply don’t get enough love. And this creamy yellow squash casserole is definitely among them, deserving a prime spot on your table.
Ingredients You Will Need
To create this delightful yellow squash casserole, you’ll need a selection of fresh vegetables, dairy products, and pantry staples. While the full, detailed list with exact measurements is available in the printable recipe card at the very end of this post, here’s a quick overview of the key components you’ll want to gather. Having all your ingredients prepped and ready before you begin will make the cooking process smooth and enjoyable.
Ingredient Info and Substitution Suggestions
Understanding each ingredient’s role and potential substitutions can help you tailor this casserole to your taste and what you have on hand.
SQUASH – For this particular recipe, we’ve opted for 6 medium-sized yellow squash, which were sliced into uniform 1/4 inch rounds. When selecting your squash, look for ones that are firm to the touch, feel heavy for their size, and have smooth, shiny skin without blemishes. Yellow summer squash is ideal for its mild flavor and quick cooking time. The 1/4-inch thickness is key; it ensures the squash cooks through to a tender consistency without becoming overly mushy, while also holding its shape beautifully in the casserole.
CHEESE – Our preference leans towards sharp cheddar cheese, as its robust flavor truly shines through the creamy base, providing a delightful zing. However, feel free to substitute with mild or extra sharp cheddar depending on your flavor preference. For those who enjoy a different cheesy profile, you can easily swap out the cheddar entirely for your favorite kind of cheese. Consider using Monterey Jack for a milder, meltier texture, Gruyere for a sophisticated nutty note, or even a Mexican blend for a different twist. A blend of two cheeses, like cheddar and mozzarella, can also offer a fantastic combination of flavor and melty goodness. The final sprinkle of Parmesan cheese adds an extra layer of salty, umami depth to the topping.
TOPPING – The buttery Ritz cracker topping is more than just a garnish; it’s an integral part of what ties this casserole together, providing an irresistible golden-brown crust and a salty, crunchy contrast to the creamy interior. The rich, slightly sweet flavor of Ritz crackers makes them a perfect choice. If Ritz crackers aren’t available or you prefer an alternative, you can substitute them with plain or seasoned breadcrumbs for a classic crunchy texture, or even crushed saltine crackers for a similar salty profile. For a gluten-free option, look for gluten-free butter crackers or use gluten-free breadcrumbs.
SOUR CREAM & EGGS – Full-fat sour cream is essential for achieving that luxurious, creamy texture and tangy depth in the casserole base. If you’re looking to lighten it up slightly, a light sour cream can be used, but note that the richness may be slightly diminished. The eggs act as a binder, helping the casserole set and hold its shape, preventing it from becoming too loose or crumbly.
SEASONING – A simple combination of sea salt, fresh thyme, and ground black pepper enhances the natural flavors of the squash and cheese without overpowering them. Fresh thyme is highly recommended for its aromatic qualities, but a pinch of dried thyme (use less, as dried herbs are more potent) can be used in a pinch. Don’t be shy about tasting and adjusting the salt and pepper to your personal preference before baking.
How to Make Squash Casserole
These step-by-step photos and instructions are here to help you visualize how to make this recipe. You can Jump to Recipe to get the printable version of this recipe, complete with measurements and instructions at the bottom.
- Preheat your oven to 400F (200°C) to ensure it’s ready to bake once your casserole is assembled. Lightly grease a 9×9 square glass baking dish with butter or non-stick spray, preparing it for a smooth release and easy cleanup.
- In a large pan, combine your sliced squash and chopped onion with 1/3 cup of water. Cook this mixture over medium-high heat for approximately 8-10 minutes, or until the squash is tender-crisp. You want it soft but not completely falling apart, as it will continue to cook in the oven. Once cooked, drain any excess water thoroughly before transferring the squash and onion to a large mixing bowl.
TIP – Squash naturally contains a lot of water, which can make your casserole watery if not properly removed. After cooking, allow the squash to sit in a strainer for a few extra minutes, gently pressing down on it with the back of a spoon to release as much moisture as possible. Be careful not to mash or squish the delicate squash slices during this process.
- While the squash drains, prepare the creamy filling. In a separate medium bowl, whisk together the shredded sharp cheddar cheese, full-fat sour cream, eggs, sea salt, fresh thyme, and ground black pepper until thoroughly combined and smooth. This mixture forms the luscious heart of your casserole. Pour this rich mixture into the bowl with the cooked squash and onion, gently folding everything together until the squash is evenly coated. If the mixture appears too liquidy after combining, you can carefully drain a small amount of the liquid to ensure a perfectly set casserole.
- Carefully transfer the squash and creamy filling mixture into the prepared 9×9 baking dish, spreading it into an even layer. Evenly sprinkle ¼ cup of grated Parmesan cheese over the top of the casserole mixture. This layer of Parmesan will add another dimension of cheesy flavor and contribute to a beautiful golden crust.
- Prepare the irresistible topping. In a small bowl, thoroughly combine the crushed Ritz crackers with the melted butter. Mix them until every cracker crumb is coated with butter, ensuring a perfectly golden and crisp topping. Sprinkle this mixture in an even layer over the casserole. Place the dish in the preheated oven and bake for approximately 15 minutes, or until the topping is beautifully golden brown and the casserole is bubbling invitingly around the edges, indicating it’s heated through and set.
- Once baked to perfection, remove the squash casserole from the oven. For a final touch of freshness and elegance, garnish with a sprinkle of fresh thyme leaves. Allow it to cool for a few minutes before serving to let the flavors meld and the casserole set further. Then, scoop out generous portions and enjoy this comforting classic!
Frequently Asked Questions & Expert Tips
A watery casserole is a common issue, primarily because squash has a very high water content. To prevent this, it’s crucial to drain the cooked squash extremely well before combining it with the other ingredients. After sautéing, allow the squash to sit in a colander for several minutes, gently pressing it down (without squishing!) to encourage more moisture release. Also, be careful not to overcook the squash in the skillet initially; it should be tender-crisp. It will continue to cook and soften in the oven, and overcooked squash tends to release even more water, potentially leading to a mushy texture.
Absolutely! You can certainly use a combination of both zucchini and yellow squash if desired. They have similar textures and flavors and will cook similarly. If you’re specifically looking for a zucchini-based dish, we also have a fantastic zucchini casserole recipe that you might enjoy!
No, there’s no need to peel the yellow squash for this recipe. The skin of yellow summer squash is thin and tender, cooking down beautifully. In fact, leaving the skin on helps the squash rounds maintain their shape and integrity after being baked, preventing them from becoming too soft or falling apart in the casserole.
Yes, this casserole is great for make-ahead preparation. You can prepare the entire casserole mixture (the squash, creamy filling, and Parmesan layer) a day in advance. Store it, tightly covered with plastic wrap, in the refrigerator. When you’re ready to bake, remove the casserole from the fridge and allow it to sit at room temperature for about 30 minutes while your oven preheats (this is especially important if using a glass dish to prevent thermal shock). Add the cracker topping just before baking. You may need to add a few extra minutes to the baking time if the casserole is going into the oven cold.
To store leftovers, ensure the casserole has cooled completely to room temperature. Then, transfer it to an air-tight container and keep it in the refrigerator for up to 3-4 days. To reheat, you can warm individual servings in the microwave, or for best results, reheat the entire dish or larger portions in a 350F (175°C) oven until warmed through and bubbly. Covering it loosely with foil during reheating can help prevent the topping from over-browning.
Yes, you can freeze squash casserole, but it’s best to do so without the cracker topping. Prepare the casserole as directed, up to the point before adding the Ritz cracker topping. Allow it to cool completely, then cover it tightly with foil and plastic wrap. It can be frozen for up to 2-3 months. When ready to serve, thaw overnight in the refrigerator, add the fresh cracker topping, and bake as usual, potentially adding an extra 10-15 minutes to the baking time.
A 9×9 inch square glass baking dish is recommended for this recipe. Its size allows for the perfect depth and ensures even cooking. If you don’t have a 9×9, an 8×8 inch dish will yield a thicker casserole and may require slightly longer baking time, while a 9×13 inch dish will result in a thinner casserole and may cook a bit faster. Always adjust baking times based on your specific dish and oven.
To make it a bit healthier, you could opt for light sour cream or even plain Greek yogurt (which also adds a nice tang and protein). You could also reduce the amount of cheese or use a lower-fat cheese option. For a dairy-free version, use dairy-free sour cream alternatives and plant-based shredded cheeses. Ensure your Ritz crackers (or alternative topping) are also dairy-free. Results may vary slightly in texture and flavor with these substitutions, but it’s definitely achievable!
Serving Suggestions
Squash casserole is incredibly versatile and makes an awesome side dish all year round. It’s a popular choice for summer gatherings, thanks to the abundance of fresh yellow squash, but it truly shines during the holidays, making it a perennial favorite.
For a festive spread, serve this comforting casserole alongside traditional holiday mains such as a succulent roasted turkey or a beautifully glazed ham. Beyond the holidays, it pairs wonderfully with a wide variety of main courses. Consider serving it with a perfectly cooked spatchcock chicken, a tender sirloin pork roast, or an elegant beef tenderloin. It also complements lighter fare like grilled fish or a hearty vegetarian main, adding a rich, creamy element that elevates the entire meal. Don’t forget a simple green salad and some crusty bread to complete the dining experience.
More Squash Recipes
If you’ve enjoyed this yellow squash casserole and are looking to explore more delicious ways to incorporate squash into your diet, here are some fantastic recipes to try:
- Zucchini Casserole
- Air Fryer Acorn Squash
- Baked Spaghetti Squash
- Butternut Squash Mac and Cheese
- Slow Cooker Butternut Squash Soup
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Squash Casserole
IMPORTANT – There are often Frequently Asked Questions within the blog post that you may find helpful. Simply scroll back up to read them!
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Ingredients
- 6 medium yellow squash sliced 1/4 inch thick
- 1 med-large yellow onion chopped
- ⅓ cup water
- 2 cups sharp cheddar cheese shredded
- 1 ½ cups sour cream full-fat
- 2 large eggs
- ½ teaspoon sea salt more to taste
- ½ Tablespoon fresh thyme
- ¼ teaspoon ground black pepper
- ½ cup parmesan cheese grated
- 30 Ritz crackers crushed
- ½ cup unsalted butter melted. 1 stick
Things You’ll Need
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9×9 baking dish
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Mixing bowls
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Large Skillet
Before You Begin
- Choose squash that are firm and feel heavy with shiny skin.
- You do not need to peel the squash for this recipe. The skin actually helps keep the squash rounds intact after being baked.
- You can substitute the sharp cheddar with mild or extra sharp if desired. Easily swap out the cheddar entirely and go with your favorite kind of cheese, or a blend of the two.
- The Ritz crackers can be substituted with breadcrumbs or saltines if preferred. For a gluten-free option, use gluten-free butter crackers or breadcrumbs.
- Squash has a high water content, which will shine through in the finished casserole if you don’t drain it well enough before combining it with the other ingredients. You’ll want to try and remove as much excess water as possible both during the sautéing process and when you drain them afterward. Keep in mind the squash will still continue to cook in the oven after sautéing so don’t overcook them in the skillet, this can cause them to become mushy.
Instructions
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Preheat the oven to 400F (200°C) and lightly grease a 9×9 square glass baking dish.
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Cook the squash and onion in a large pan with 1/3 cup water on medium-high heat for about 8-10 minutes or until soft. Strain any excess water thoroughly before placing them in a large mixing bowl.
TIP – You may want to allow the squash to sit in the strainer for a few minutes to get the majority of the water out, and lightly press them down without squishing them.
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In a medium bowl, mix together the shredded cheddar cheese, sour cream, eggs, salt, thyme, and ground black pepper. Pour this creamy mixture into the bowl with the squash and onion and combine well. If the mixture becomes very liquidy after combining, you can drain some of it out.
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Transfer the squash mixture to the prepared baking dish and spread it evenly. Cover the top with ¼ cup of grated Parmesan cheese.
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In a small bowl, combine the crushed Ritz crackers and melted butter well, ensuring all crumbs are coated. Sprinkle an even layer of this buttery cracker mixture on top of the casserole. Bake for about 15 minutes or until the topping is golden brown and the casserole is bubbling around the edges.
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Garnish with more fresh thyme, if desired, and enjoy your delicious squash casserole.
Expert Tips & FAQs
- Store any cooled leftovers in an air-tight container kept in the refrigerator for up to 3-4 days. Reheat in a 350F oven until warmed through.
- To Make Ahead – Prepare the casserole without the cracker topping a day in advance and store it, covered, in the refrigerator. Allow the casserole to rest at room temp while the oven preheats (or slightly longer if you are using a glass dish) then proceed with recipe instructions. You may need to add a few extra minutes in the oven if it’s going in cold.
- Freezing Tip: For freezing, prepare the casserole without the cracker topping. Cool completely, then wrap tightly and freeze for up to 2-3 months. Thaw in the refrigerator before adding the topping and baking.
- Preventing Wateriness: The key is thorough draining of the sautéed squash. Gently press out excess liquid in a colander.
- Choosing Squash: Opt for firm, heavy yellow squash with smooth, shiny skin for the best texture and flavor.
Nutrition
The recipes on this blog are tested with a conventional gas oven and gas stovetop. It’s important to note that some ovens, especially as they age, can cook and bake inconsistently. Using an inexpensive oven thermometer can assure you that your oven is truly heating to the proper temperature. If you use a toaster oven or countertop oven, please keep in mind that they may not distribute heat the same as a conventional full sized oven and you may need to adjust your cooking/baking times. In the case of recipes made with a pressure cooker, air fryer, slow cooker, or other appliance, a link to the appliances we use is listed within each respective recipe. For baking recipes where measurements are given by weight, please note that results may not be the same if cups are used instead, and we can’t guarantee success with that method.