Vegetarian Breakfast Casserole

Reason You’ll Love This Recipe

There are many reasons to love this veggie egg casserole, but here are four of my favorites.

• Easy to prepare. After the veggies cook, throw them into a casserole dish with the egg mixture and bake! Easy!
• Delicious. The veggies, cheese, and spices give this vegetable breakfast casserole fantastic flavor!
• Healthy. If you’re looking for a high protein, low carb, gluten-free breakfast option, this is it! 
• Easily adaptable. Swap in and out ingredients with what you have on hand.
• Make-ahead champion! Assemble the ingredients the night before for brunch or make it on Sunday to eat all week.

Ingredients

Here are the ingredients you need to make this vegetarian breakfast bake.

• Olive oil. I prefer olive oil to saute the veggies, but you can use any healthy oil.
• Veggies. I use a mix of mushrooms, red bell peppers, onion, and broccoli in this veggie breakfast casserole, but you can use any of your favorite vegetables. I’ll give more options in the variations section.
• Eggs. I use large whole organic eggs for the best results.
• Greek yogurt. Years ago, a family member gave me an egg casserole recipe that included Greek yogurt- delicious! It creates a fantastic flavor and gives the eggs a creamy texture, so I add it to just about all the egg bakes I make.
• Seasoning. A blend of garlic powder, onion powder, salt, and pepper gives this veggie breakfast casserole another delicious layer of flavor.
• Sharp cheddar cheese. For the best results, shred the cheese fresh.

How to Make Vegetarian Egg Casserole

• Preheat the oven to 350 degrees.
• Spray a 9 x 13 ceramic baking dish with cooking spray and set aside.
• In a large skillet, heat one tablespoon of olive oil over medium heat. Add the sliced mushrooms and cook until tender, about 5 minutes. Place the cooked mushrooms into the baking dish.

• Using the same pan, heat the last tablespoon of olive oil over medium heat. Add the onion and bell pepper and cook until the onion is translucent and both vegetables are tender. Add the broccoli to the pan with the onions and peppers. Break up the broccoli into small pieces as it cooks thoroughly. 
• Add the vegetables to the baking dish with the mushrooms.

• In a large mixing bowl (you can do this while the vegetables are cooking), whisk the eggs, greek yogurt, garlic powder, onion powder, salt, and pepper.
• Pour the egg mixture over the vegetables, add the cheese, and then give it a couple of slow stirs. You can sprinkle some cheese on top.

• Place the dish into the oven and bake for 45 – 55 minutes or until the center is set.
• Serve hot. Sprinkle with green onions, if you want.

Serving Suggestions

When I prepare this vegetarian breakfast bake for brunch, these are my favorite recipes to serve on the side:

• Yogurt bowls with homemade almond butter granola.
• A bowl of vanilla overnight oats with berries.
• A variety of baked oatmeal cups.
• Homemade turkey breakfast sausage.
• Healthy french toast bake.
• Homemade hash browns or oven-roasted crispy potatoes.

Cooking Tips

• Don’t skip prepping the vegetables beforehand. I highly recommend cooking the vegetables first before adding the egg bake. Vegetables tend to release a lot of liquid, so adding them raw could release too much liquid into the egg mixture. Also, cooking the vegetables first allows you to add more flavor. 
• Remove as much liquid from the cooked veggies as possible before adding them to the egg casserole. Too much liquid will result in a mushy egg bake!

Variations

• Add more flavor by roasting the vegetables. This does take a little longer, but it’s a great way to add another layer of flavor. I mix the vegetables with a tablespoon of olive oil and then roast them in the oven for about 30 minutes in a 400-degree oven. I love throwing in Italian roasted veggies into this egg veggie bake when I have leftovers
• Swap in your favorite vegetable. Cauliflower, sweet potato, spinach, kale, leeks, corn, tomatoes, artichokes, and asparagus are tasty options.
• Use sour cream in place of greek yogurt. This will add more fat and calories, but it will still be delicious.
• To reduce the fat and calories, you can use half egg whites and half whole eggs. I’ve made many egg casseroles replacing half the eggs with egg whites, and it’s still just as tasty! You might want to add a couple more egg whites to make up for the yolks not being used.
• Use frozen vegetables. Cook or thaw the frozen veggies and ensure the vegetables and the liquid is gone before stirring them into the egg bake.
• Add meat to this veggie egg casserole. Cooked chicken sausage, bacon, and breakfast sausage are all great options.
• Use your favorite cheese. Feta cheese, swiss cheese, gouda, mozzarella cheese, pepper jack, and provolone are all great options.
• Spice it up by adding crushed red pepper flakes or a couple of dashes of hot sauce.
• To make the egg breakfast casserole dairy-free substitute dairy-free yogurt or coconut milk and vegan cheese. Or you can leave the cheese out.
• For extra fiber stir in a cup of cooked quinoa.

Make ahead & Storage Tips

Egg casseroles are one of my favorite breakfast recipes to make ahead of time. 

For the following day: Assemble the ingredients into a casserole dish and then cover and refrigerate. In the morning, continue with the recipe. Because the casserole is cold, you might need to add a few more minutes to the cooking time.

Or you can cook the vegetables ahead of time. This way, when you’re ready to put the egg bake together, all you need to do is whisk up the eggs, stir in the vegetables, and bake.

For the week: After the breakfast casserole cooks, let it cool down, slice it up, and store it in glass meal prep containers for the week. In the morning, take a slice and warm it up for 1-2 minutes in the microwave. 

For the freezer: Slice the cooled veggie egg casserole into portions, wrap it in plastic, and then place it into a freezer bag—label it and freeze for up to 3 months. Reheat in the microwave for 1-3 minutes or until hot.

More Egg Breakfast Recipes

• Vegetarian Breakfast Burrito
• Freezer Breakfast Burrito
• Sausage Egg Cups
• Frozen Breakfast Sandwiches

Check out more healthy breakfast recipes!