Veggie Breakfast Casserole (Delicious & Simple)

Name: Veggie Breakfast Casserole (Delicious & Simple)
Prep time: 10 min
Cook time: 35 min
Total time: 45 min
Cuisine: American
Ingredients: 1 tbsp olive oil; 1 medium onion (peeled and diced); 1 red bell pepper (diced); 1 green bell pepper (diced); 1 cup mushrooms (sliced); 12 large eggs; 1/4 cup milk (2% or your choice); 1 tsp kosher salt; 1/2 tsp black pepper; 1 cup cherry tomatoes (quartered); 1/2 cup shredded mozzarella cheese

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A veggie breakfast casserole is the perfect dish for holidays, meal prep, or a hearty breakfast any day of the week. Packed with fresh vegetables, eggs, and cheese, this easy breakfast bake is flavorful, healthy, and simple to make!

Why You’ll Love This Recipe

Easy to make – Takes just 10 minutes to prep.
Customizable – Use your favorite vegetables and cheeses.
Perfect for meal prep – Make it ahead for a stress-free breakfast.
Great for feeding a crowd – Ideal for holidays and gatherings.

Ingredients

For the best results, use fresh, high-quality ingredients:

1 tablespoon olive oil
1 medium onion (peeled and diced)
1 red bell pepper (diced)
1 green bell pepper (diced)
1 cup mushrooms (sliced)
12 large eggs
¼ cup milk (2% or your choice)
1 teaspoon kosher salt
½ teaspoon black pepper
1 cup cherry tomatoes (quartered)
½ cup shredded mozzarella cheese

Step-by-Step Instructions

1. Prepare the Oven and Baking Dish

Preheat the oven to 375°F (190°C). Spray a 9×13-inch baking dish with nonstick spray and set aside.

2. Cook the Vegetables

A close-up of a sautéed vegetable dish in a black frying pan, featuring sliced mushrooms, diced red and green bell peppers, and chopped onions, seasoned with black pepper and garnished with fresh herbs.

Heat olive oil in a nonstick skillet over medium heat.
Add onions and sauté for 2-3 minutes until soft.
Stir in bell peppers and mushrooms and cook for 4-5 minutes until tender.
Season with salt and pepper, then remove from heat and let cool slightly.

3. Whisk the Eggs

Whisking eggs and milk in a ceramic bowl with cheese and eggs nearby.

In a mixing bowl, whisk together eggs, milk, salt, and pepper.

4. Assemble the Casserole

A colorful veggie-packed breakfast bake, featuring layers of eggs, roasted peppers, and mushrooms, served on a rustic wooden table.

Spread the cooked vegetables evenly in the prepared baking dish.
Add cherry tomatoes on top.
Pour the egg mixture over the vegetables.
Sprinkle shredded cheese on top.

5. Bake

A sliced breakfast casserole with vibrant vegetables and fluffy eggs, garnished with fresh herbs and served with a side of toast.

Bake for 30-35 minutes or until the eggs are set and slightly golden around the edges.
Let cool for 5 minutes before slicing and serving.

Variations & Substitutions

Make it dairy-free – Use almond, oat, or coconut milk and dairy-free cheese.
Add protein – Include crumbled sausage, bacon, or turkey.
Use different veggies – Try spinach, kale, zucchini, or asparagus.
Add potatoes – Mix in diced cooked potatoes for a heartier dish.

Frequently Asked Questions

1. Can I make this egg casserole ahead of time?

Yes! Prepare the casserole the night before, cover, and store in the fridge. Bake fresh in the morning, adding 5-10 extra minutes if baking directly from the fridge.

2. Can I use different vegetables in this casserole?

Absolutely! Great additions include:
Spinach or kale
Zucchini or shredded carrots
Broccoli or asparagus
Jalapeños for a spicy kick

3. How do I prevent the egg casserole from being watery?

To avoid excess moisture:
Sauté the vegetables first to release moisture.
Drain liquid from mushrooms and peppers after cooking.
If using frozen veggies, thaw and pat them dry before adding.

4. Can I make this egg casserole dairy-free?

Yes! Omit the cheese or use dairy-free cheese, and swap the milk for unsweetened almond, oat, or coconut milk.

5. How do I store and reheat leftovers?

Store in an airtight container in the fridge for up to 4 days.
Reheat in the microwave (30-60 seconds) or oven (350°F for 10 minutes).

6. Can I freeze this egg casserole?

Yes! Let the casserole cool completely, then slice into portions. Wrap in plastic wrap, place in a freezer bag, and freeze for up to 3 months. Reheat in a 350°F oven for 15-20 minutes or microwave for 1-2 minutes.

Related Recipes

If you loved this veggie breakfast casserole, try these delicious breakfast ideas:

Overnight Eggs Benedict Casserole

Final Thoughts

Check out the original Veggie Breakfast Casserole recipe here. This veggie breakfast casserole is a simple, healthy, and delicious way to start your day! Perfect for meal prep, holidays, or a family breakfast.