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This yellow squash casserole is both comforting and indulgent. Rich, creamy layers of tender, sliced yellow squash are topped by golden, buttery crackers adding a delightful crunch with every bite. Each bite is a burst of deliciousness!
This is a perfect dinner for the summer. It’s a comforting side dish or main dish that is perfect for potlucks, family dinners, or any other special occasion. This budget-friendly recipe is a great way to use up your healthy and nutritious squash.
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Yellow squash casserole is a popular Southern dish that’s normally made with sliced yellow squash, onions, and sometimes other vegetables, and mixed with sour cream, mayonnaise, eggs, and cheese. It is then topped with buttery crackers and baked in a casserole dish until it is golden brown and bubbly.
- Yellow squash: This yellow summer squash has a mild, slightly sweet taste that is perfect for this recipe.
- Butter: I used salted butter for this recipe but you can also use unsalted butter and add salt to taste. You can also use olive oil instead of butter.
- Sweet onion: This compliments the mild sweetness of the squash but you can also use yellow onion.
- Salt and black pepper: Add these to taste. Some people like to add cayenne pepper for an extra layer of flavor.
- Eggs: This acts as a binder and prevents the dish from being excessively moist.
- Sour cream: Enhances the creaminess of the casserole and gives it a yummy flavor.
- Mayonnaise: Helps make the dish extra creamy.
- Garlic powder and thyme: These add an extra layer of flavor. You can also use creole seasoning, cayenne powder, and other fresh herbs like rosemary if you prefer.
- Cheddar cheese: sharp or mild, depending on preference. We like the taste of sharp cheddar cheese but you can use the kind you prefer. You can also substitute with melty cheeses like Monterey Jack, Colby cheese, Gruyere, or Mozzarella.
- Ritz crackers: These round buttery crackers elevate the dish by giving it a nice crunchy texture and delicious flavor. Cover the casserole dish with aluminum foil if you notice that the cracker topping is browning fast and the eggs in the casserole haven’t set.
In a large skillet, melt butter over medium heat. Sauté sliced squash and diced onion in the melted butter until the squash is tender. Drain the excess liquid in the squash by placing it in a colander.
In a medium bowl, whisk the eggs, sour cream, mayonnaise, garlic powder, thyme, and cheddar cheese. Mix well to combine.
Add this cheese mixture to the squash mixture and stir it in until well combined. Transfer the uncooked casserole to your prepared baking dish.
In a small bowl, crumble the buttery round crackers. Melt the remaining tablespoons of the butter and mix with the cracker crumbs.
In an even layer, sprinkle the buttery cracker crumb mixture on top of the casserole. Bake the casserole in the preheated oven for 35-40 minutes until the cracker topping is golden brown.
You certainly can. Simply wrap it in plastic wrap and cover it with aluminum foil and place it in the fridge for not more than 1 day. Before baking, let it sit on the counter for about 30 minutes until it reaches room temperature, then bake it according to the recipe instructions.
Yes, you can! It should last in the freezer for about 3 months. To reheat, thaw it in the fridge overnight or let it sit on the counter for 30 minutes until it reaches room temperature, then bake it in the oven at 350 degrees for 40-45 minutes.
Consider using zucchini for this recipe or using half zucchini and half yellow squash for this recipe! Squash and zucchini share similarities in taste and texture and are both highly nutritious. Zucchini tends to have a bit more water content, so it would be best to remove the seeds from the center of the zucchini before slicing them.
Ritz Cracker Variations
Though Ritz crackers are most ideal for this dish, you can use any other kind of buttery crackers or substitute them with cornflakes or Panko bread crumbs. Some people like to add crumbled crispy fried onions for extra flavor.
Squash Casserole Sides
Grilled chicken, grilled fish, roasted potatoes, fried chicken, pork chops, steamed veggies, garlic bread, a green salad, fluffy rice, or quinoa are just a few items that go really well with this recipe.
Squash Casserole Recipe
- 7" x 11" casserole dish (or a similar size rectangular shape casserole dish)
- Mandolin or sharp knife
- Mixing bowl
- 6 yellow squash, sliced
- 4 tablespoons butter
- 1 cup sweet onion, diced
- ½ teaspoon salt
- ¼ teaspoon pepper
- 2 eggs
- ¼ cup sour cream
- ¼ cup mayonnaise
- 1 teaspoon garlic powder
- ½ teaspoon thyme
- 1 cup cheddar cheese, shredded
- 1 sleeve Ritz crackers, crushed
- Preheat your oven to 350℉
- Spray your casserole dish with cooking spray.
- Slice the fresh squash into thin even slices. A great way to do this is to use a mandolin which will give you even thickness. Or, a sharp knife works too.
- In a large skillet, melt 2 tablespoons of butter over medium heat.
- Sauté the squash slices and diced onion in the melted butter until the squash is tender. Drain the excess liquid in the squash
- In a medium bowl, whisk the eggs, sour cream, mayonnaise, garlic powder, thyme and cheddar cheese. Mix well to combine.
- Add this cheese mixture to the squash mixture and stir it in until well combined.
- Transfer the uncooked casserole to your prepared baking dish.
- In a small bowl, crumble the buttery round crackers. Melt the remaining tablespoons of the butter and mix with the cracker crumbs.
- In an even layer, sprinkle the buttery cracker crumb mixture on top of the casserole.
- Bake the casserole in the preheated oven for 35-40 minutes until the cracker topping is golden brown and the squash casserole mixture has set.
Nutrition information is automatically calculated, so should only be used as an approximation.