Sunday Baked Vegetable Casserole

Name: Sunday Baked Vegetable Casserole
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Yield: 6 servings
Ingredients: 2 cups broccoli florets; 1 cup chopped carrots; 1 cup diced bell peppers; 1 cup sliced mushrooms; 2 cups cooked quinoa; 2 cups shredded cheese (cheddar or mozzarella); 1 cup milk; 3 eggs; 1/2 cup breadcrumbs; Salt and pepper to taste; 2 tablespoons olive oil; 1 teaspoon garlic powder; 1 teaspoon dried oregano

Highlighted under: Baking & Desserts

I love whipping up this Sunday Baked Vegetable Casserole as a comforting family meal to kick off the week. The vibrant mix of colorful vegetables comes together beautifully, creating a hearty dish that's both healthy and satisfying. It’s perfect for using up any leftover veggies I have in the fridge. The rich, cheesy top layer is my favorite part, melting perfectly with each bite. Trust me, this casserole will become a staple in your Sunday dinner rotation.

Created by

Lydia Spencer

Last updated on 2026-01-13T22:28:08.329Z

When I first made this casserole, I was thrilled to see how easily it came together, and even more delighted by the delicious outcome! Layering the vegetables with the creamy sauce creates a wonderful blend of flavors and textures. I find that letting it bake long enough for the top to brown gives the dish an irresistible crunch.

Each Sunday, I browse my kitchen for whatever fresh veggies are around, and it often leads to delightful surprises in flavor combinations. If you’re looking to up the flavor, fresh herbs really elevate the dish, making it even more enjoyable for family meals or potlucks.

        Why You'll Love This Recipe
        A colorful array of vegetables makes this dish both nutritious and visually appealing.
The creamy, cheesy topping is absolutely irresistible and comforting.
It's a great way to use up leftover veggies while feeding your family a delicious meal.

      

Choosing Your Vegetables

One of the joys of making this Sunday Baked Vegetable Casserole is the flexibility it offers with vegetable combinations. You can use fresh, frozen, or even leftover vegetables, which helps avoid waste and allows for seasonal variations. Consider adding zucchini, spinach, or even sweet potatoes for a different flavor profile. The key is to ensure that whatever vegetables you choose are chopped into similar sizes to ensure even cooking and a uniform texture throughout the casserole.

Keep in mind that firmer vegetables like carrots and bell peppers should be sautéed a bit longer than mushrooms or delicate greens. Sautéing them first not only enhances their flavor but also helps them soften, ensuring they blend well with the creamy, cheesy mixture.

Understanding the Cheese Topping

The choice of cheese greatly impacts the final flavor of your casserole. While cheddar provides a sharp, tangy taste, mozzarella offers a gooey, stretchy texture that's hard to resist. For a deeper flavor, you might consider mixing in some grated Parmesan or even a bit of feta for a tangy twist. The blend of cheeses can also create a more complex flavor profile, making each bite more delightful.

When layering the cheese on top, be generous—this is what creates that deliciously bubbly, gooey surface that contrasts beautifully with the tender vegetables below. To achieve a perfect golden brown crust, broil the casserole for the last few minutes of baking. Just keep an eye on it to prevent burning; it can go from golden to charred in a matter of seconds!

Make-Ahead and Storage Tips

This casserole is an excellent candidate for meal prep. You can assemble the entire dish the day before and refrigerate it, then simply pop it in the oven when you’re ready to cook. If you go this route, consider reducing the baking time by about 5-10 minutes to account for the cold ingredients. It can also be frozen before baking—just wrap it tightly in foil. When you're ready to bake, thaw it overnight in the fridge before cooking as usual; this ensures even cooking.

Leftovers can be stored in an airtight container in the fridge for up to four days, making it a fantastic option for packed lunches or quick dinners. To reheat, pop it in the oven at 350°F (175°C) until warmed through, about 20-25 minutes, or microwave individual portions for a speedy meal.

Ingredients

Gather the following ingredients to make this delicious casserole:

Vegetable Casserole Ingredients

2 cups broccoli florets
1 cup chopped carrots
1 cup diced bell peppers
1 cup sliced mushrooms
2 cups cooked quinoa
2 cups shredded cheese (cheddar or mozzarella)
1 cup milk
3 eggs
1/2 cup breadcrumbs
Salt and pepper to taste
2 tablespoons olive oil
1 teaspoon garlic powder
1 teaspoon dried oregano

Now that you have everything ready, let's move on to the cooking steps!

Instructions

Follow these steps to prepare your baked vegetable casserole:

Preheat the Oven

Preheat your oven to 375°F (190°C) and lightly grease a baking dish with olive oil.

Sauté the Vegetables

In a skillet, heat 2 tablespoons of olive oil over medium heat. Add the chopped carrots, bell peppers, and mushrooms. Sauté for about 5-7 minutes until slightly softened.

Combine Ingredients

In a large bowl, mix together the sautéed vegetables, quinoa, garlic powder, oregano, salt, and pepper. Stir in the milk and eggs until well combined.

Layer and Bake

Transfer the mixture to the prepared baking dish. Top with shredded cheese and breadcrumbs. Bake in the preheated oven for 30-35 minutes or until the top is golden brown.

Cool and Serve

Once baked, allow the casserole to cool for about 10 minutes before serving. Enjoy!

Your delicious Sunday Baked Vegetable Casserole is ready to be enjoyed!

Pro Tips

For added flavor, consider incorporating different vegetables or spices based on what you have on hand. Fresh herbs like basil or thyme can also enhance the aroma and taste beautifully.

Vegetarian and Dietary Swaps

This casserole is already vegetarian and can easily be adapted for vegan diets as well. To do this, substitute the eggs with flaxseed meal or a commercial egg replacer. For the cheese, look for plant-based cheese options that melt well. Additionally, use almond milk or coconut milk instead of regular milk for a creamier texture without dairy. These swaps mean everyone can enjoy this comforting dish regardless of dietary preferences!

If you'd like to add a protein element, consider incorporating lentils or chickpeas. Simply mix in a cup of cooked lentils to boost the protein content without altering the flavor significantly. Not only does this enhance the nutritional value, but it also gives the casserole an interesting texture.

Serving Suggestions

Serve this baked vegetable casserole as a standalone dish or pair it with a fresh garden salad for a complete meal. A simple vinaigrette can elevate the lightness of the salad, providing a nice contrast to the richness of the casserole. You might also consider adding a side of crusty bread or garlic bread for a comforting touch.

For a heartier meal, serve it alongside grilled chicken or fish. If you're going vegetarian, a side of quinoa or a bean salad can complement the casserole beautifully. The combination of flavors and textures makes for an inviting table setting perfect for family gatherings or casual get-togethers.

Questions About Recipes

→ Can I use frozen vegetables instead?

Yes, frozen vegetables work well, but make sure to thaw and drain them thoroughly before adding to the casserole.

→ How long does the casserole last in the fridge?

It can be stored in the refrigerator for up to 3 days in an airtight container.

→ Can I make this casserole ahead of time?

Absolutely! You can prepare it a day in advance and store it in the fridge. Just bake it when you’re ready to serve.

→ What can I serve with the casserole?

This casserole is great on its own, but you can also serve it with a fresh salad or bread on the side for a more complete meal.