Sunday Baked Vegetable Casserole

Name: Sunday Baked Vegetable Casserole
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Yield: 4 servings
Ingredients: 2 cups of chopped mixed vegetables (e.g., bell peppers, zucchini, carrots); 1 cup of chopped onion; 2 cups of fresh spinach; 1 cup of diced tomatoes; 1 cup of shredded cheese (optional); 2 tablespoons of olive oil; 1 teaspoon of garlic powder; Salt and pepper to taste; 1 teaspoon of dried Italian herbs; 1 cup of cooked quinoa or rice (optional)

Highlighted under: Baking & Desserts

I absolutely love making this Sunday Baked Vegetable Casserole because it brings the family together for a wholesome meal. Each bite is a delightful mix of fresh veggies that are baked to perfection, making it a vibrant addition to our Sunday dinner table. The aroma that fills the kitchen while it bakes is truly comforting, and it’s often the highlight of our weekend feasts. Plus, it’s a perfect way to use whatever seasonal vegetables I have on hand. It’s one of those dishes that everyone enjoys!

Created by

Freya Cooper

Last updated on 2026-01-13T18:25:21.150Z

This Sunday Baked Vegetable Casserole has become a beloved staple in our home. When creating this dish, I experimented with various vegetables and spices to bring out the best flavor combinations. The layering technique I use ensures every piece is bursting with taste, and baking it all together creates a beautiful medley of textures.

One key tip I learned is to pre-cook the firmer vegetables slightly before baking, as this allows for even cooking and prevents any crunchiness in the final dish. I also love adding a sprinkle of cheese or breadcrumbs on top for that extra crunch and flavor!

        Why You Will Love This Recipe
        Vibrant mix of fresh seasonal vegetables
Hearty and satisfying for the whole family
Easy to customize with your favorite ingredients

      

Understanding Your Ingredients

The choice of vegetables in this casserole is essential for achieving a balanced flavor and texture. Bell peppers, zucchini, and carrots not only add vibrant color but also bring their own unique sweetness and crunch. While these are recommended, feel free to experiment with seasonal produce like asparagus or butternut squash. Just ensure that any vegetables you substitute have similar cooking times to avoid uneven textures in the final dish.

Fresh spinach plays a vital role in this casserole by adding a nutrient boost and a mild, earthy flavor. If you find yourself with stale spinach, consider using frozen spinach instead; just make sure to thaw and drain it thoroughly to avoid extra moisture. This will help maintain the desired consistency of your casserole, preventing it from becoming soggy.

Perfecting the Baking Process

When you assemble the casserole, spreading the mixture evenly in the baking dish is crucial for even cooking. If you prefer a crispy top, consider using a broiler for the last 2-3 minutes of baking. Monitor closely during this time to prevent burning. The goal is to achieve a bubbly, golden top that contrasts beautifully with the tender vegetables below.

After baking for 30-40 minutes, the edges of your casserole should be gently bubbling, and the top should appear set. If it hasn’t reached this point, an extra 5-10 minutes in the oven may be necessary. Letting it rest for a few minutes after removing it from the oven allows the flavors to meld further and makes it easier to serve.

Ingredients

Main Ingredients

2 cups of chopped mixed vegetables (e.g., bell peppers, zucchini, carrots)
1 cup of chopped onion
2 cups of fresh spinach
1 cup of diced tomatoes
1 cup of shredded cheese (optional)
2 tablespoons of olive oil
1 teaspoon of garlic powder
Salt and pepper to taste
1 teaspoon of dried Italian herbs
1 cup of cooked quinoa or rice (optional)

Feel free to adjust the vegetables according to your preference or what you have on hand!

Instructions

Preheat Oven

Preheat your oven to 375°F (190°C).

Prepare the Vegetables

In a large skillet, heat olive oil over medium heat and sauté the onions until translucent. Add the mixed vegetables and cook for about 5 minutes, stirring occasionally.

Combine Ingredients

In a large bowl, combine the sautéed vegetables, fresh spinach, diced tomatoes, cooked quinoa or rice, garlic powder, Italian herbs, salt, and pepper. Mix until well combined.

Assemble the Casserole

Transfer the mixture to a baking dish and top with shredded cheese if desired. Spread evenly.

Bake

Bake in the preheated oven for 30-40 minutes or until the top is golden and bubbly.

Serve

Let it cool for a few minutes before serving. Enjoy your delicious Sunday Baked Vegetable Casserole!

Serve hot as a main dish or side with your favorite protein!

Pro Tips

Try to use a variety of colorful vegetables to not only enhance the visual appeal but also to maximize the nutritional benefits.

Dietary Adjustments

This casserole is highly adaptable for various dietary needs. For a vegan option, simply replace the cheese with a dairy-free alternative or omit it altogether, as the dish is full of flavors without being cheese-dependent. Additionally, for gluten-free diners, ensure your quinoa or rice is certified gluten-free, as cross-contamination can occur during processing.

If you're looking to increase the protein content, consider adding cooked lentils or chickpeas. This not only enhances the nutritional value but also provides a heartier texture that complements the softness of the baked vegetables.

Make-Ahead and Storage Tips

This casserole can easily be prepared in advance, making it an ideal choice for busy weekends. After assembling, cover it tightly with aluminum foil and store it in the refrigerator for up to 24 hours before baking. This resting period allows flavors to develop, and cooking time remains the same when you bake it from chilled.

For longer storage, this dish freezes well. I recommend freezing before baking and using a freezer-safe dish. When you’re ready to eat it, thaw in the refrigerator overnight and bake as per the instructions, adding a few extra minutes if needed to ensure it’s heated through.

Questions About Recipes

→ Can I make this casserole ahead of time?

Yes, you can prepare the casserole a day ahead and store it in the refrigerator. Just bake it before serving.

→ What vegetables work best in this recipe?

You can use a variety of vegetables like broccoli, cauliflower, or even seasonal vegetables like butternut squash.

→ Can I freeze leftovers?

Absolutely! You can freeze the casserole for up to three months. Just thaw and reheat in the oven before serving.

→ Is this recipe vegetarian?

Yes, the Sunday Baked Vegetable Casserole is vegetarian-friendly. You can add meat if you desire!