Piece of Vegetable Egg Casserole on a plate

We had the most glorious Sunday last week! Hey, if you’re lucky enough to have a random 50+ degree day in February (in the Midwest, anyway!), you’re lucky enough.

We had the doors and windows wide open, BIRDS WERE CHIRPING, and a solo afternoon walk turned into an invigorating run that I did not want to come home from. Man, fresh air does wonders for the soul!

More snow is on the way today, and my ankles still hurt from the ambitious workout (never underestimate the power vitamin D and a killer playlist can have on one’s perceived running capabilities,) but I’m still riding high from that day and can’t help but think of spring, fresh food, and Vegetable Egg Casserole. Doesn’t this look like spring on a plate?

overhead photo of breakfast casserole on a plate

I’m still trying to make good on my goal to eat a little less meat in 2020, which is easy to do with recipes like this in my repertoire. Sauteed mushrooms, peppers, and onions combine with hash browns, eggs, milk, and cheese to create a meatless yet hearty breakfast, brunch, or dinner. Vegetarian or not, this Vegetable Egg Casserole will satisfy anyone. Cheese tends to hold that power!

This recipe makes an enormous amount of food – I use an 11×17″ baking dish though have separated it into two smaller baking dishes before – so it’s perfect for feeding a crowd. That said, it also reheats wonderfully if you want to make on a Sunday for ready-made breakfasts all week long. Additionally, it’s easy to halve. Flexible, packed with vegetables, and oh-so-scrumptious – you ready to eat?

Piece of Vegetable Egg Casserole with a bite taken out of it

How to Make Vegetable Egg Casserole:

Start by sauting 16oz sliced mushrooms in a very large skillet until they release their liquid. Once the liquid has cooked off, season with salt and pepper then continue to saute until the mushrooms are golden brown and tender. Scoop into a bowl then set aside.

Psst: I got this 12″ high-sided Le Creuset Skillet for Christmas and it is my very favorite thing on the planet right now. Big enough to cook for my family of five, plus the high sides really reduce splatter. Highly recommend!

Heat another Tablespoon extra virgin olive oil in the skillet then add 2 bell peppers that have been seeded and chopped – I use one red and one green – plus a chopped white or yellow onion. Season with lots of salt and pepper then saute until tender. Spread the mixture out onto a plate to cool slightly.

Meanwhile, crack 12 eggs into an enormous bowl then add 1/2 cup milk plus salt and pepper. I usually use ~3/4 teaspoon salt. Whisk everything up to combine.

Next stir in a 30oz bag frozen hash browns that have been thawed (I use Ore-Ida brand) plus 8oz each shredded mozzarella and cheddar cheese. 

Lastly, add the sauteed vegetables then stir to combine.

Scoop the mixture into a nonstick sprayed 11×17″ baking dish, or two smaller baking dishes, then sprinkle 4oz shredded mozzarella and cheddar cheese on top, cover with nonstick sprayed foil, and bake for 50-60 minutes or until the center has set.

Remove the foil then bake for another couple of minutes, to fully melt the cheese, then slice and serve. I like to serve my Vegetable Egg Casserole with fresh green onions, salsa, or a scoop of guacamole. YUM. However you eat it, I hope you love this hearty, veggie-packed dish – enjoy!

Piece of breakfast casserole with a fork

Similar Recipes

Vegetable Egg Casserole


Vegetable Egg Casserole is a meatless version of my favorite egg casserole recipe. Packed with peppers, onions, and mushrooms, it will satisfy all tastes!


serves a crowd

  • 2 Tablespoons extra virgin olive oil, divided
  • 16oz mushrooms, sliced
  • salt and pepper
  • 2 bell peppers (any color), seeded and chopped
  • 1 yellow or white onion, chopped
  • 12 eggs
  • 1/2 cup milk
  • 30oz bag gluten-free frozen hash browns, thawed
  • 12oz shredded mozzarella cheese, divided
  • 12oz shredded cheddar cheese, divided


  1. Preheat oven to 350 degrees then spray an 11x17" baking dish (or 2 medium-size baking dishes) with nonstick spray and set aside.
  2. Heat 1 Tablespoon oil in a very large skillet over heat that's just a touch above medium. Add mushrooms then saute until they have released their liquid and the liquid has cooked off. Season with salt and pepper then continue to saute until the mushrooms are golden brown and tender. Scoop into a bowl then set aside.
  3. Heat remaining Tablespoon oil in skillet then add peppers and onions. Season with salt and pepper then saute until crisp tender, adding an extra drizzle of extra virgin olive oil and/or turning the heat down slightly if the vegetables begin to burn. Spread vegetables onto a plate to cool slightly.
  4. In a HUGE bowl, whisk together eggs, milk, salt, and pepper (I usually use ~3/4 teaspoon salt). Add hash browns and 8oz of each cheese to the bowl then stir to combine. Add sauteed vegetables then stir to combine. Pour mixture into prepared baking dish then sprinkle the top with remaining shredded cheese and cover with a piece of nonstick sprayed foil. Bake for 50-60 minutes, or until the center is set, then remove foil and bake for an additional 2-3 minutes or until cheese is fully melted. If you are using two smaller baking dishes, start checking for doneness around 40 minutes. Let casserole sit for 10 minutes before slicing and serving.


  • I like to serve this breakfast casserole with chopped green onions, guacamole, or salsa.

This recipe is courtesy of Iowa Girl Eats, http://iowagirleats.com.

Photo collage of Vegetable Egg Casserole