Sunday Baked Vegetable Casserole

Highlighted under: Baking & Desserts

I absolutely love making this Sunday Baked Vegetable Casserole for my family. It's a delightful way to celebrate the end of the week with a warm, comforting dish packed with seasonal vegetables. The best part? The creamy sauce and crunchy topping make every bite incredibly satisfying. I enjoy switching up the vegetable combinations based on what I have on hand, ensuring that each casserole is unique. You can easily customize this recipe for picky eaters, too. It's a fantastic way to both please everyone and use up those odds and ends from the fridge.

Jasmine Porter

Created by

Jasmine Porter

Last updated on 2026-01-13T20:28:15.918Z

When I first experimented with a baked vegetable casserole, I was amazed at how combining just a few simple ingredients could create such a hearty dish. I used a mix of zucchini, bell peppers, and mushrooms, and the result was a flavorful explosion that my family couldn't get enough of. The key to a perfect casserole is ensuring you have a good balance of textures, so I crisped some breadcrumbs for the topping.

Since that first trial, I've played around with different cheese blends and herbs, finding that adding fresh basil made a remarkable difference in flavor. This recipe can be easily adjusted to suit any dietary restrictions, making it a favorite in my home to satisfy all taste buds!

Why You'll Love This Casserole

  • A colorful medley of seasonal vegetables
  • Creamy and rich sauce that binds everything together
  • Perfect for meal prep or entertaining guests

Technique Tips for Perfect Texture

Achieving a perfectly baked casseroled dish relies significantly on proper vegetable preparation. Ensure your vegetables are cut uniformly; this guarantees they cook evenly. When sautéing, aim for a golden color on the edges of the vegetables, which usually takes about 5-7 minutes on medium heat. If they start to brown too quickly, simply lower the heat to avoid burning, which can alter the flavor of your dish.

Another key technique is to properly layer the ingredients. Start with the sautéed vegetables at the bottom, which helps create a flavorful base, as they will release moisture while baking. Pour the creamy sauce over the top, making sure every piece is coated. This ensures the casserole has a rich, cohesive flavor, beautifully binding all the elements for a deliciously smooth bite.

Ingredient Substitutions

If you're looking to customize your casserole based on dietary preferences or ingredient availability, there are several substitutions that work well here. For a lighter version, consider using half-and-half instead of heavy cream. It will slightly alter the richness but still provide a creamy texture. For a dairy-free alternative, coconut cream can work, though it may add a hint of coconut flavor.

Vegetable flexibility is another key feature of this dish. If zucchini isn't in season, yellow squash can be used as a substitute. Got extra broccoli or cauliflower? These cruciferous vegetables can easily replace the mushrooms or bell peppers, adding their unique textures and flavors. Don’t hesitate to experiment; each combination can yield a new favorite!

Make-Ahead and Storage Tips

This casserole is a fantastic make-ahead meal. You can prepare it up to a day in advance. Simply sauté the vegetables, layer them with the sauce, and assemble everything in your baking dish, then cover it tightly with plastic wrap and refrigerate. When ready to bake, remove the wrap and add the topping before placing it in the oven; it might require an extra 5-10 minutes of baking time due to being cold.

If you have leftovers, store them in an airtight container in the fridge for up to 3 days. Reheating can be done in the microwave, but for the best texture, I recommend using the oven. Simply cover the casserole with foil and bake at 350°F (175°C) for about 15-20 minutes, or until warmed through, which will help retain that delightful crusty topping.

Ingredients

Gather the following ingredients to prepare your casserole.

Vegetable Ingredients

  • 2 cups zucchini, diced
  • 1 cup bell peppers, chopped
  • 1 cup mushrooms, sliced
  • 1 cup spinach, chopped
  • 1 onion, diced
  • 2 cloves garlic, minced

Casserole Sauce

  • 2 cups heavy cream
  • 1 cup shredded mozzarella cheese
  • 1 cup grated Parmesan cheese
  • 1 teaspoon Italian seasoning
  • Salt and pepper to taste

Topping

  • 1 cup breadcrumbs
  • 2 tablespoons olive oil
  • 1/2 cup grated Parmesan cheese

Once you've gathered all your ingredients, you're all set to get started!

Instructions

Follow these steps to create your delicious baked vegetable casserole.

Prepare the Oven

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

Sauté Vegetables

In a large skillet, heat a tablespoon of olive oil over medium heat. Add onions and garlic, cooking until translucent. Stir in the zucchini, bell peppers, mushrooms, and spinach, and sauté until softened.

Make the Sauce

In a bowl, combine the heavy cream, mozzarella cheese, Parmesan cheese, Italian seasoning, salt, and pepper. Mix well.

Combine Ingredients

In the greased baking dish, layer the sautéed vegetables and pour the sauce over them. Ensure the vegetables are well coated.

Prepare Topping

In a small bowl, mix the breadcrumbs with olive oil and Parmesan cheese. Sprinkle evenly over the casserole.

Bake

Bake in the preheated oven for 35-40 minutes, or until the topping is golden brown and the sauce is bubbling. Allow cooling for a few minutes before serving.

Enjoy your hearty Sunday Baked Vegetable Casserole!

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Pro Tips

  • For a lighter version, substitute heavy cream with low-fat milk or a dairy-free alternative. Feel free to add your favorite herbs for extra flavor!

Serving Suggestions

This Sunday Baked Vegetable Casserole pairs beautifully with a simple side salad or crusty bread to soak up the delicious sauce. For a heartier meal, serve it alongside grilled chicken or fish, which contrasts nicely with the creamy greens. I often find that a sprinkle of fresh herbs like basil or parsley just before serving adds a burst of freshness and color.

Leftovers can also be creatively repurposed. Chop up the casserole into smaller bites and mix with scrambled eggs for a tasty breakfast hash or toss it into a wrap for a quick and easy lunch option. The versatility of this dish ensures that it can adapt to your meal planning throughout the week.

Troubleshooting Common Issues

If your casserole appears too dry, it may benefit from an extra splash of cream or vegetable broth during the assembly to ensure moisture throughout the baking process. Remember that every oven can be slightly different; check for doneness and adjust baking times accordingly. Look for a bubbly surface and a golden-brown topping, which indicates that it’s ready to serve.

In the case the topping becomes overly browned before the dish finishes baking, simply cover it loosely with aluminum foil to prevent further browning while the casserole continues to cook thoroughly. This can help retain that delightful crunch while ensuring the flavors meld perfectly.

Questions About Recipes

→ Can I use frozen vegetables for this recipe?

Yes, using frozen vegetables is a convenient option. Just make sure to thaw and drain them properly before mixing.

→ How do I store leftovers?

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in the oven or microwave before serving.

→ Can I make this casserole ahead of time?

Absolutely! You can assemble it the night before, cover, refrigerate, and bake it the following day.

→ What other vegetables can I use?

Feel free to add any vegetables you like, such as broccoli, carrots, or corn for additional flavor and nutrition.

Sunday Baked Vegetable Casserole

I absolutely love making this Sunday Baked Vegetable Casserole for my family. It's a delightful way to celebrate the end of the week with a warm, comforting dish packed with seasonal vegetables. The best part? The creamy sauce and crunchy topping make every bite incredibly satisfying. I enjoy switching up the vegetable combinations based on what I have on hand, ensuring that each casserole is unique. You can easily customize this recipe for picky eaters, too. It's a fantastic way to both please everyone and use up those odds and ends from the fridge.

Prep Time20 minutes
Cooking Duration45 minutes
Overall Time1 hour 5 minutes

Created by: Jasmine Porter

Recipe Type: Baking & Desserts

Skill Level: Intermediate

Final Quantity: 6 servings

What You'll Need

Vegetable Ingredients

  1. 2 cups zucchini, diced
  2. 1 cup bell peppers, chopped
  3. 1 cup mushrooms, sliced
  4. 1 cup spinach, chopped
  5. 1 onion, diced
  6. 2 cloves garlic, minced

Casserole Sauce

  1. 2 cups heavy cream
  2. 1 cup shredded mozzarella cheese
  3. 1 cup grated Parmesan cheese
  4. 1 teaspoon Italian seasoning
  5. Salt and pepper to taste

Topping

  1. 1 cup breadcrumbs
  2. 2 tablespoons olive oil
  3. 1/2 cup grated Parmesan cheese

How-To Steps

Step 01

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

Step 02

In a large skillet, heat a tablespoon of olive oil over medium heat. Add onions and garlic, cooking until translucent. Stir in the zucchini, bell peppers, mushrooms, and spinach, and sauté until softened.

Step 03

In a bowl, combine the heavy cream, mozzarella cheese, Parmesan cheese, Italian seasoning, salt, and pepper. Mix well.

Step 04

In the greased baking dish, layer the sautéed vegetables and pour the sauce over them. Ensure the vegetables are well coated.

Step 05

In a small bowl, mix the breadcrumbs with olive oil and Parmesan cheese. Sprinkle evenly over the casserole.

Step 06

Bake in the preheated oven for 35-40 minutes, or until the topping is golden brown and the sauce is bubbling. Allow cooling for a few minutes before serving.

Extra Tips

  1. For a lighter version, substitute heavy cream with low-fat milk or a dairy-free alternative. Feel free to add your favorite herbs for extra flavor!

Nutritional Breakdown (Per Serving)

  • Calories: 320 kcal
  • Total Fat: 22g
  • Saturated Fat: 12g
  • Cholesterol: 80mg
  • Sodium: 300mg
  • Total Carbohydrates: 20g
  • Dietary Fiber: 3g
  • Sugars: 4g
  • Protein: 10g