Quick Benefits
Parmesan Squash Casserole is a wholesome and nutritious dish, perfect for any meal of the day. It’s packed with vitamins from fresh squash and tomatoes while delivering a creamy, cheesy indulgence without excessive calories. This dish is easy to prepare, making it a great choice for weeknight dinners or potlucks. Plus, it’s an excellent way to use up an abundance of summer squash!
Essential Ingredients
To make this delicious Parmesan Squash Casserole, gather the following ingredients:
- 4 yellow squash and/or zucchini (about 8 cups sliced)
- 1 tablespoon olive oil
- 1 tablespoon minced garlic
- 1 tablespoon fresh thyme leaves or 1/2 teaspoon dried thyme
- Salt to taste
- 2 tomatoes, sliced
- 2 eggs
- 1/3 cup sour cream
- 1 cup crumbled feta cheese
- 2 tablespoons grated Parmesan cheese
- 1 tablespoon lemon juice
- Salt and pepper

Preparation Steps
- Preheat the oven to 375 degrees Fahrenheit. Spray a large casserole dish with nonstick spray to prevent sticking.
- Prepare the squash: Slice the squash into 1/4-inch rounds. If the squash is large, cut it in half before slicing.
- Sauté the vegetables: Heat olive oil in a large non-stick frying pan over medium heat. Add the sliced squash, minced garlic, and thyme, seasoning with salt to taste. Sauté until the squash starts to soften but still retains texture.
- Add the tomatoes: Remove the pan from heat and mix in the sliced tomatoes to introduce juiciness to the dish.
- Prepare the egg mixture: In a medium bowl, beat together eggs, sour cream, crumbled feta cheese, grated Parmesan cheese, and lemon juice until well combined.
- Layer the casserole: Place half of the sautéed squash mixture into the prepared casserole dish. Season with salt and pepper, then pour half of the egg mixture over it. Repeat the layering with the remaining squash and egg mixture.
- Add extra cheese (optional): Sprinkle additional feta and Parmesan cheese on top for extra flavor.
- Bake the casserole: Place the dish in the preheated oven and bake for 40-45 minutes, or until the mixture is bubbling and slightly set.
- Serve hot and enjoy!
Health Benefits
- Rich in Nutrients: Squash is high in fiber, vitamins A and C, and antioxidants that promote good health.
- Lower in Calories: Compared to traditional casseroles, this dish is lower in carbs and calories while still being rich in flavor.
- Protein-Packed: Eggs, feta, and Parmesan cheese provide a good amount of protein, making it a well-balanced meal.
- Gut-Friendly: The dish contains probiotics from feta cheese, which can support gut health.
Serving Suggestions
- Serve as a main dish alongside a crisp green salad or warm crusty bread to soak up the creamy sauce.
- Pair with grilled chicken or fish for a protein boost.
- Enjoy as a brunch dish the next morning—simply reheat individual servings for a delicious, quick breakfast.
- Serve it at potlucks or family gatherings straight from the baking dish for a warm, shareable meal.
Creative Variations
- Add Protein: Mix in cooked sausage, ground turkey, or shredded chicken for a heartier casserole.
- Try Different Cheeses: Swap feta for goat cheese or cheddar for a different flavor profile.
- Make it Spicier: Add a pinch of red pepper flakes or chopped jalapeños for a bit of heat.
- Add Fresh Herbs: Basil or parsley can bring extra freshness to the dish.
- Go Low-Carb: Skip the tomatoes and add spinach or mushrooms for a keto-friendly version.
Storage Tips
- Refrigeration: Store leftovers in an airtight container in the fridge for up to 3 days.
- Reheating: Warm individual portions in the microwave or bake in an oven at 350°F for 10-15 minutes.
- Freezing: This casserole freezes well! Wrap tightly and store for up to 2 months. Thaw overnight in the fridge before reheating.
Pro Tips
- Avoid Overcooking Squash: Slightly undercook the squash during sautéing to prevent it from becoming mushy in the casserole.
- Use Fresh Ingredients: Fresh thyme and garlic will enhance the overall taste compared to dried substitutes.
- Drain Excess Moisture: If your squash releases too much liquid, drain it slightly before adding to the casserole to maintain texture.
- Make it Crispier: For a crispier top, broil the casserole for the last 3-5 minutes of baking.
Frequently Asked Questions
Can I use only zucchini or only yellow squash?
Yes! You can use just zucchini, just yellow squash, or a combination of both, depending on what you have available.
Can I make this dish ahead of time?
Absolutely! You can assemble the casserole a day ahead and store it covered in the refrigerator. Just bake it when you’re ready to serve.
Is there a dairy-free option?
Yes, you can substitute the sour cream with a dairy-free yogurt and use nutritional yeast instead of Parmesan cheese.
Can I make this casserole vegetarian?
Yes! The dish is naturally vegetarian, but you can add plant-based protein sources like lentils or chickpeas for extra protein.
Enjoy this Parmesan Squash Casserole, a comforting, cheesy, and nutritious dish perfect for any occasion!
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Parmesan Squash Casserole
Parmesan Squash Casserole is a wholesome and nutritious dish, perfect for any meal of the day. It’s packed with vitamins from fresh squash and tomatoes while delivering a creamy, cheesy indulgence without excessive calories. This dish is easy to prepare, making it a great choice for weeknight dinners or potlucks. Plus, it’s an excellent way to use up an abundance of summer squash!
- Total Time: 55-60 minutes
Ingredients
4 yellow squash and/or zucchini (about 8 cups sliced)
1 tablespoon olive oil
1 tablespoon minced garlic
1 tablespoon fresh thyme leaves or 1/2 tsp dried thyme
Salt to taste
2 tomatoes, sliced
2 eggs
1/3 cup sour cream
1 cup crumbled feta cheese
2 tablespoons grated Parmesan cheese
1 tablespoon lemon juice
Salt and pepper
Instructions
Preheat your oven to 375 degrees Fahrenheit. Don’t forget to spray a large casserole dish with nonstick spray to ensure easy serving and less cleanup afterward. Now, slice your squash into 1/4-inch rounds. If you’ve got some larger squash, just slice them in half before cutting them into smaller pieces.
Heat your olive oil in a large non-stick frying pan over medium heat. Ah, that lovely scent of oil heating! Add in your sliced squash, minced garlic, and fresh thyme leaves, seasoning it all with salt to taste. Sauté gently, stirring until the squash begins to soften—but be careful not to overdo it. We want the squash to retain some of its delightful texture.
Once the squash has softened a bit, remove the pan from heat and introduce your sliced tomatoes. They’ll add a lovely juiciness to the dish.
Now grab a medium-sized bowl, and beat together your eggs, sour cream, crumbled feta cheese, grated Parmesan cheese, and lemon juice. Mix well until everything is combined and creamy.
Layer half of your sautéed squash mixture into the bottom of the prepared casserole dish. Sprinkle some salt and pepper over this layer, then pour half of the egg mixture on top. Repeat this layering with the remaining squash and egg mixture.
To finish, if you’re feeling indulgent, top the casserole with a bit of extra crumbled feta and grated Parmesan cheese for that extra touch of flavor!
Bake in the preheated oven for about 40-45 minutes. You’ll know it’s ready when the mixture is bubbling and slightly set. Serve it hot, and enjoy the creamy, cheesy goodness that is Parmesan Squash Casserole.
- Prep Time: 15 minutes
- Cook Time: 40-45 minutes
- Category: Main Dish, Side Dish
- Cuisine: American, Mediterranean
Nutrition
- Serving Size: 10 servings
- Calories: 180 per serving