Roasted Zucchini and Summer Squash Casserole

Name: Roasted Zucchini and Summer Squash Casserole
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Ingredients: 1 large zucchinis (sliced into 1/4 inch rounds); 1 larges yellow squash ( sliced into ¼ inch rounds); 3 to 5 Italian tomatoes (hulled, seeded, sliced into 1/4 inch); 2 red onion (sliced into 1/4 inch); 1/4 cup olive oil; 1 tsp onion powder; 1 tsp garlic powder; Salt and pepper from the mill; 1/2 cup cheddar cheese (grated ); 1/4 cup parmesan (grated )

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With this roasted zucchini and summer squash casserole, you can savor the delightful flavors, the melding of tender roasted vegetables and the savory blend of cheeses will make the dish a family favorite.

Cheesy Summer Squash and Zucchini Casserole in a white plate with lettuce at the bottom

Packed with an assortment of thinly-sliced, zucchini, yellow squash, onion, and tomatoes. The vegetables are baked until they soften up but don’t lose their freshness.

This recipe is an excellent side dish to pair with this Tofu Steak

Why you will love this recipe

The delicious side dish is a straightforward and easy recipe to follow, making it perfect for both experienced cooks and beginners. With just a few simple steps, you'll have a great side dish ready to serve.

The colorful medley of roasted vegetables creates a visually stunning baked casserole that's not only delicious but also aesthetically pleasing, making it an impressive dish for any occasion.

If you happen to have leftovers, you can store and reheat the vegetable dish for another delicious meal, ensuring that none of the tasty goodness goes to waste

The ingredients

You will need these simple ingredients you can easily find at your grocery store to make this roasted zucchini and summer squash casserole.

Notes on the ingredients

Zucchini and fresh yellow squash: Sliced zucchini and summer squash are the star ingredients of this casserole, providing a mild, slightly sweet flavor and a tender texture when roasted. Choose firm and fresh zucchini and squash for the best results.

Italian Tomatoes: Using Italian tomatoes adds a burst of juiciness and acidity to the casserole, complementing the sweetness of the squash. Removing the seeds and excess moisture ensures the casserole doesn't become too watery during baking.

Red Onions: Red onions bring a touch of color and a mild onion flavor to the casserole. Their sweetness becomes more pronounced when roasted.

Onion Powder and Garlic Powder: These powdered seasonings provide a convenient way to add onion and garlic flavors to the dish, the best part is there is no need for chopping or mincing.

Cheddar Cheese: Adding cheddar cheese is the perfect way to add a delicious sharpness and creaminess to the casserole. It melts beautifully, forming a golden and slightly crispy topping.

Parmesan Cheese: Parmesan cheese is known for its nutty and savory flavor, which adds depth to the dish. When grated and combined with cheddar, it forms a delectable cheese crust.

How to make the roasted zucchini and summer squash casserole; Step by Step

zucchini and summer squash sliced on a wooden board.

Begin by preheating your oven to 375°F (190°C). Grease a medium-sized baking dish lightly with olive oil to ensure your casserole doesn't stick.
Wash and slice the zucchini, yellow squash, Italian tomatoes, and red onions into uniform ¼-inch rounds. The even thickness ensures even cooking.

sliced vegetables in a baking dish ready to be cooked.

Take your vegetables and layer them in the prepared baking dish, alternating between zucchini, yellow squash, tomatoes, and red onions. The combination of colors will create a visually appealing presentation.
Cover the baking dish with foil and place it in the preheated oven. Allow the casserole to roast for approximately 20 minutes. This will give the vegetables time to become tender and infused with the delicious seasoning.

Baked casserole out of the oven, in a baking dish top view

After 20 minutes, remove the foil and sprinkle the grated cheddar and parmesan cheeses over the top. Pop the dish back into the oven for an additional 10 minutes, or until the cheese is melted and golden brown.

Serve and enjoy: Once your roasted zucchini and summer squash casserole is cooked to perfection, take it out of the oven and let it cool slightly. Serve it as a side dish to complement your main course.

Tips

Here are some helpful tips to ensure your roasted zucchini and summer squash casserole turns out perfectly:

Try to slice the zucchini, yellow squash, tomatoes, and onions into uniform ¼-inch rounds. This helps in even cooking and ensures all the vegetables have a consistent texture.
Choose fresh vegetables for the best flavor and texture. Farmers' markets are great places to find high-quality produce during the summer months.
When layering the vegetables in the baking dish, consider arranging them in an overlapping pattern. This not only looks beautiful but also helps the flavors to mingle during baking.
Keep an eye on the casserole while it's baking. The baking time may vary depending on your oven's temperature and the thickness of the vegetables. You want the vegetables to be tender but not mushy.

Variations

Add some crumbled feta cheese, and a sprinkle of dried Italian seasoning to the casserole for a Mediterranean flair. The tangy feta complement the roasted vegetables beautifully.

If you enjoy some heat, sprinkle red pepper flakes or drizzle hot sauce over the casserole before baking. The spiciness will add a delightful contrast to the sweetness of the roasted veggies.

Experiment with various fresh herbs like thyme, rosemary, or dill to infuse this easy side dish with different herbal aromas and flavors.

Add sliced ham or turkey between the veggies slices for a complete meal

Instead of just adding cheese on top, create layers of cheese between the vegetable slices. Try mozzarella, provolone, or fontina to make the casserole ooey-gooey and even more flavorful.

Garnish with sour cream.

Serving

This casserole can shine as the star of a vegetarian main dish. Serve generous portions alongside a fresh green salad and some crusty bread for a complete and satisfying meal.

Pair the casserole with grilled or roasted meats, such as chicken, steak, or fish. It complements the main course beautifully.

Storage

Allow the leftover casserole to cool to room temperature before storing. Transfer any remaining portions to an airtight container or cover the baking dish with plastic wrap or foil. Refrigerate within two hours of cooking. The casserole can be safely stored in the refrigerator for 3 to 4 days. However, for the best quality and taste, it's recommended to consume it within 2 to 3 days.

I do not recommend freezing this zucchini squash casserole as the texture will change and the vegetables will get to mushy.

Casserole close-up served in a white plate

FAQ's

How can I make my veggies uniform?

If you’re a perfectionist and want all the veggies to have a uniform look, try using a mandolin to get the same diameter for each slice. Ideally, each slice should be about ¼ inch in diameter.

Can I use different types of cheese for the topping?

While the recipe calls for cheddar and parmesan cheese, feel free to experiment with other cheese varieties like mozzarella, gruyere, or feta for unique flavor profiles.

Can I serve this easy casserole cold?

While the casserole is best served warm, you can also enjoy it at room temperature as part of a picnic or cold buffet spread.

Mediterranean Flavors