Sunday Baked Vegetable Casserole

Name: Sunday Baked Vegetable Casserole
Prep time: 15 min
Cook time: 45 min
Total time: 1 h
Yield: 8 servings
Ingredients: 2 cups chopped zucchini; 1 cup diced bell peppers; 1 cup chopped spinach; 1 cup diced tomatoes; 1 cup chopped onion; 4 large eggs; 1 cup shredded cheese (cheddar or mozzarella); 1 cup milk; 1 teaspoon garlic powder; 1 teaspoon dried oregano; Salt and pepper to taste; Olive oil for greasing

Highlighted under: Baking & Desserts

I love making this Sunday Baked Vegetable Casserole when the weekend rolls around. It’s hearty, satisfying, and packed with vibrant colors from fresh vegetables. The aroma that fills the kitchen while it bakes is irresistible! This dish not only brings my family together at the table but also allows me to use up any leftover vegetables in the fridge. The combination of flavors is delightful, and it's always a hit, whether for breakfast, lunch, or dinner—perfectly versatile for any occasion.

Created by

Madeline Archer

Last updated on 2026-01-13T21:55:11.719Z

When I first experimented with this casserole, I wanted something that wasn't just nutritious but also bursting with flavor. I decided to opt for a variety of seasonal vegetables, like zucchini and bell peppers, which add different textures and tastes to the dish. I was amazed by how a sprinkle of fresh herbs transformed the entire flavor profile!

This recipe is incredibly forgiving, so I encourage you to adapt it based on what you have on hand. One important tip: let it rest for a few minutes after baking to help it set up perfectly, making it easier to slice and serve. Enjoy discovering your own variations!

        Why You Will Love This Recipe
        Hearty and colorful combination of vegetables
Flexible recipe that adapts to your taste preferences
Comforting dish perfect for any meal of the day

      

Choosing the Right Vegetables

One of the best aspects of this Sunday Baked Vegetable Casserole is its versatility with vegetables. While I love using zucchini, bell peppers, and spinach, you can easily substitute or add your favorites based on what you have on hand. Carrots, mushrooms, or even broccoli work beautifully in this dish. Just be sure to chop them into similar sizes to ensure even cooking.

Freshness is key for achieving that vibrant color and satisfying crunch in your casserole. Selecting a mix of seasonal vegetables not only enhances the flavor but also nourishes your body with fresh nutrients. When preparing, aim for a balance of textures; combining both softer vegetables like tomatoes with firmer ones like zucchini can create a delightful eating experience.

Egg Mixture Tips

The egg mixture is what binds the casserole together, so using the right proportions is essential for a perfect consistency. Make sure to whisk the eggs and milk thoroughly until smooth; this will ensure that the casserole sets properly during baking. If you prefer a richer flavor, you can use half-and-half instead of milk.

For a unique twist, consider adding different herbs or spices to the egg mixture. Fresh herbs like basil or thyme can elevate the dish further. However, be cautious with the salt; many cheeses are already salty, so taste as you go. This careful balancing of flavors will result in a casserole that’s not only hearty but incredibly satisfying.

Serving and Storage Suggestions

Once your casserole is baked to golden perfection, let it cool slightly before slicing. Serving it warm allows the flavors to meld a bit more, enhancing each bite. It pairs wonderfully with a light salad or crusty bread, making it suitable for brunch or a cozy dinner. If you have leftovers, they make a delightful breakfast option when heated in the microwave for a quick start to your day.

For make-ahead enthusiasts, this casserole can be prepped a day in advance. Simply assemble the dish, cover it tightly, and store it in the refrigerator. On baking day, just pop it in the oven—this can save you precious time during busy weekends. Additionally, this casserole freezes well; portion it out before freezing for easy reheating whenever you need a comforting meal.

Ingredients

Vegetables

2 cups chopped zucchini
1 cup diced bell peppers
1 cup chopped spinach
1 cup diced tomatoes
1 cup chopped onion

Other Ingredients

4 large eggs
1 cup shredded cheese (cheddar or mozzarella)
1 cup milk
1 teaspoon garlic powder
1 teaspoon dried oregano
Salt and pepper to taste
Olive oil for greasing

Instructions

Preheat the Oven

Preheat your oven to 375°F (190°C). Grease a 9x13 inch baking dish with olive oil.

Prepare the Vegetables

In a large bowl, combine the chopped zucchini, bell peppers, spinach, tomatoes, and onion. Gently mix until evenly combined.

Whisk the Egg Mixture

In another bowl, whisk together the eggs, milk, garlic powder, oregano, salt, and pepper until well blended.

Combine and Pour

Add the vegetable mixture to the egg mixture, and then pour the entire mixture into the prepared baking dish. Top with shredded cheese.

Bake

Bake in the preheated oven for 40-45 minutes, or until the casserole is set in the middle and the top is golden.

Let It Rest

Remove the casserole from the oven and let it rest for about 10 minutes before slicing. Serve warm and enjoy!

Pro Tips

For an extra burst of flavor, consider adding fresh herbs like basil or parsley before serving. You can also substitute the cheese with a vegan option to make this dish dairy-free.

Achieving the Perfect Bake

Baking the casserole at 375°F (190°C) for 40–45 minutes allows the eggs to set properly while giving the top a beautiful golden color. Keep an eye on it in the last 10 minutes of baking; if the edges are browning too quickly, cover the dish loosely with aluminum foil to prevent burning.

You’ll know it’s done when a knife inserted in the center comes out clean. If you're unsure, there's no harm in checking a minute or two earlier—an overcooked casserole can become dry and lose that delightful creaminess from the egg mixture.

Flavor Enhancements

To add an extra layer of flavor, consider incorporating a layer of sauce, such as a marinara or a cheesy béchamel, between the vegetable and egg layers. This not only moistens the casserole but adds richness as it bakes, creating a more complex flavor profile that elevates the dish further.

Experimenting with different cheeses can also make a big difference. Feta or goat cheese could be used instead of cheddar or mozzarella for a tangy finish. You might also mix cheeses to create a more interesting taste experience. Just ensure that the total amount remains around one cup to maintain the desired texture.

Questions About Recipes

→ Can I use frozen vegetables in this recipe?

Yes, you can use frozen vegetables! Just make sure to thaw and drain them well before adding to the mixture.

→ Can I make this casserole ahead of time?

Absolutely! You can prepare it the night before and refrigerate it. Just ensure to add a few extra minutes to the baking time.

→ How can I store leftovers?

Store any leftovers in an airtight container in the fridge for up to 3 days. You can reheat it in the oven or microwave.

→ Can I add meat to this casserole?

Yes, you can definitely add cooked meat! It pairs well with chicken, bacon, or sausage for added protein.