Creamy Squash & Zucchini Ritz Casserole

Creamy Squash & Zucchini Ritz Casserole is the ultimate comfort food that transforms fresh summer vegetables into a rich, cheesy, and irresistibly crunchy side dish. Tender yellow squash and zucchini are gently cooked until perfectly soft, then combined with a creamy cheese sauce and topped with buttery crushed Ritz crackers that bake into a crisp golden crust. Whether you’re serving it alongside roasted chicken, grilled steak, holiday ham, or enjoying it as a vegetarian main course, this casserole is always a crowd favorite. It’s simple enough for a weeknight dinner yet elegant enough for family gatherings and potlucks.

Prep Time: 20 minutes

Cook Time: 35 minutes

Total Time: 55 minutes

Servings: 6–8

Ingredients

For the Vegetable Filling

3 medium yellow squash, sliced into thin rounds

3 medium zucchini, sliced into thin rounds

1 small onion, finely diced

2 cloves garlic, minced

2 tablespoons butter

1 tablespoon olive oil

Salt, to taste

Black pepper, to taste

For the Creamy Mixture

1 cup sour cream

½ cup mayonnaise

1½ cups shredded sharp cheddar cheese

½ cup shredded mozzarella cheese

¼ cup grated Parmesan cheese

1 teaspoon garlic powder

½ teaspoon onion powder

½ teaspoon paprika

1 teaspoon dried thyme

For the Ritz Topping

1½ sleeves Ritz crackers, crushed

4 tablespoons melted butter

2 tablespoons grated Parmesan cheese

1 tablespoon chopped fresh parsley (optional)

Instructions

Preheat your oven to 375°F (190°C) and lightly grease a 9×13-inch baking dish.

Heat butter and olive oil in a large skillet over medium heat. Add the diced onion and cook for about 4 minutes until softened. Stir in the garlic and cook for another 30 seconds until fragrant.

Add the sliced squash and zucchini to the skillet. Season lightly with salt and black pepper. Cook for 6 to 8 minutes, stirring occasionally, until the vegetables begin to soften and release some of their moisture. Remove from heat and allow them to cool slightly.

In a large mixing bowl, combine the sour cream, mayonnaise, cheddar cheese, mozzarella, Parmesan, garlic powder, onion powder, paprika, and dried thyme. Stir until smooth and well blended.

Fold the cooked vegetables into the creamy cheese mixture, making sure every piece is evenly coated.

Transfer the mixture into the prepared baking dish and spread it into an even layer.

In a separate bowl, combine the crushed Ritz crackers with melted butter, Parmesan cheese, and chopped parsley. Toss until the crumbs are evenly coated.

Sprinkle the buttery cracker mixture evenly over the casserole.

Bake uncovered for 30 to 35 minutes, or until the filling is bubbling around the edges and the topping is crisp and golden brown.

Allow the casserole to rest for about 10 minutes before serving. This helps the filling set while keeping it creamy.

Serve warm with grilled meats, roasted chicken, baked fish, or a fresh garden salad.

Tips

For the best texture, slice the squash and zucchini evenly so they cook at the same rate.

Avoid overcooking the vegetables during sautéing. They will continue cooking in the oven, and overcooked squash can become mushy.

If your squash releases a lot of liquid, drain it well or pat it dry with paper towels before mixing it into the cheese filling.

Freshly grated cheese melts much more smoothly than pre-shredded cheese and creates a creamier casserole.

Crush the Ritz crackers into medium-sized pieces instead of fine crumbs to achieve a crispier topping.

A small pinch of cayenne pepper adds gentle warmth without making the casserole spicy.

For an extra crispy topping, broil the casserole for 1 to 2 minutes at the end of baking while watching carefully.

Let the casserole rest before serving so the creamy filling thickens slightly and slices neatly.

Fresh herbs like parsley, thyme, or chives brighten the rich flavors beautifully.

Store leftovers in an airtight container and reheat in the oven to maintain the crunchy topping.

Variations

Add cooked shredded chicken or diced turkey to transform the casserole into a complete one-dish meal.

Mix cooked crumbled bacon into the filling for smoky flavor and extra richness.

Substitute Monterey Jack, Colby Jack, Gouda, or Swiss cheese for different flavor profiles.

Use crushed buttery crackers mixed with panko breadcrumbs for an even crispier topping.

Stir sautéed mushrooms into the filling for a deeper, earthy flavor.

Add chopped spinach or kale for extra vegetables and color.

Mix in diced roasted red peppers for a touch of sweetness.

Replace sour cream with plain Greek yogurt for a lighter version with extra protein.

Add fresh jalapeños or crushed red pepper flakes if you enjoy a little heat.

Top with extra Parmesan during the final 10 minutes of baking for an even cheesier golden crust.

Q&A

Can I make this casserole ahead of time?

Yes. Assemble the casserole up to one day ahead, cover, refrigerate, and add the cracker topping just before baking.

Can I freeze this casserole?

Yes. Freeze before baking without the cracker topping. Add fresh crackers when ready to bake.

How do I prevent a watery casserole?

Cook the vegetables first and drain any excess liquid before mixing them with the creamy filling.

Can I use only zucchini or only yellow squash?

Absolutely. Either vegetable works well on its own if that’s what you have available.

Can I substitute Greek yogurt for sour cream?

Yes. Plain Greek yogurt provides a tangy flavor while reducing the fat content.

What can I serve with this casserole?

It pairs wonderfully with grilled chicken, baked ham, pork chops, steak, roasted turkey, or fresh salads.

Can I add more vegetables?

Certainly. Mushrooms, spinach, broccoli, bell peppers, and corn all make delicious additions.

How should leftovers be stored?

Refrigerate in an airtight container for up to 4 days.

Can I reheat individual portions?

Yes. Reheat in the oven or air fryer for the crispiest topping, or microwave for convenience.

Can I make it gluten-free?

Yes. Use gluten-free buttery crackers and verify that all other ingredients are certified gluten-free.

Nutrition

Approximate per serving

Calories: 340

Protein: 11g

Carbohydrates: 16g

Fat: 27g

Saturated Fat: 11g

Fiber: 3g

Sugar: 6g

Sodium: 470mg

Calcium: 240mg

Conclusion

Creamy Squash & Zucchini Ritz Casserole is a comforting side dish that combines fresh garden vegetables with a rich, cheesy filling and a buttery cracker topping that’s crisp in every bite. It’s easy to prepare, family friendly, and versatile enough for weeknight dinners, holiday feasts, or potluck gatherings. With its creamy texture, savory flavor, and satisfying crunch, this casserole is sure to become a favorite recipe you’ll make again and again.