This Easy Breakfast Casserole is a lifesaver for busy weeks and/or holiday mornings.

You can prep this breakfast the day before and then bake it the morning of a holiday. Or, you can prep the whole dish on a weekend and enjoy it all week long.

Diced onion, red and green bell peppers, and creamy gold potatoes with crumbled sausage, egg, and cheddar cheese.

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Can I Prep This Breakfast Casserole the Day Before?

Yes! One of the great things about making a breakfast casserole is that you can prep it the night before. Simply follow Steps 1, and 3-8. Cook the onion, peppers, potatoes, and sausage. Then, mix it all in a greased casserole dish and refrigerate overnight.

In the morning, whisk together the egg mixture and pour over the sausage and vegetables. Sprinkle over the cheddar cheese. Bake for 30 minutes covered in foil. Then, remove the foil and cook an additional 25 minutes until browned on top, or once the center has completely set. Test with a toothpick.

What Can I Put In a Breakfast Casserole?

Another great thing about making a breakfast casserole is you can personalize it to your liking. Don't like onion? Leave it out. Want meatless? Go for it, and add more veggies in place of the meat. Want more meat? Now we're talking. Here are some additions you could try:

Crumbled bacon
Ham
Mushrooms
Chopped spinach (only fresh, not frozen because of water content)
Green onion
Your favorite spices such as rosemary or Italian seasoning
Cherry tomatoes
Your favorite cheeses (Pepper jack, mozzarella, Monterey jack, etc.)

While you can make any additions you want, I recommend always leaving in potatoes. This is because they help to soak up any excess moisture and provide structure to the casserole. You can use diced or shredded potatoes. However, if using shredded; be sure to squeeze out as much moisture as possible before browning. *You can either dice your potatoes yourself (like I did to save money) or buy a bag of already prepared breakfast potatoes.

Tip: Be careful adding in a lot of vegetables, as too much water content will make this casserole not set up properly.

How to Make:

Prep: Grease a 9x13 casserole dish with butter or nonstick cooking spray. Dice onion and bell peppers. Chop potatoes into even bite-sized pieces. Set aside.
If cooking the same day: Preheat oven to 375 F.
Heat a large frying pan over medium-high heat with one tbsp. of oil.

Sauté onion and bell peppers until just about fork tender. Then, place it in the prepared casserole dish.

To the same pan, add another tbsp. of oil. Cook potatoes until browned and fork tender (about 10-12 minutes), stirring frequently to prevent burning. Then, place it in the casserole dish. Tip: If the potatoes are browning too quickly and aren't tender yet, turn the heat down to low and place a lid on the pan. Cook for 5 more minutes, or until fork tender.

To the same pan, add sausage. Cook the sausage, crumbling as you go, until browned and completely cooked through. Place in casserole dish.
Mix all of the ingredients in the casserole dish until evenly distributed. Smooth into an even layer.
Place the casserole dish in the fridge until ready to cook (can leave it overnight). If cooking right away, disregard this step.

When ready to cook: Preheat oven to 375 F. In a large mixing bowl; whisk eggs, milk or half & half, and salt and pepper until smooth. Pour evenly over the sausage-veggie mixture. Add shredded cheese to the top of the egg casserole.

Cover with foil and bake for 35 minutes, or until the edges have set. Remove foil and bake an additional 25-30 minutes, or until cooked through in the center. Test with a toothpick for doneness. You can also broil the last 5 minutes to encourage even more browning. Tip: All oven temperatures vary, so keep an eye on your casserole. If browning too much, you can cover it again with foil.

Enjoy within 3-4 days. Serve with your favorite sauce (ketchup, hot sauce, etc.)

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Easy Breakfast Casserole - Sausage, Egg, and Cheese

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Prep Time: 1

Cook Time: 1

Total Time: 2

Yield: squares

This Easy Breakfast Casserole is a lifesaver for busy weeks and/or holiday mornings. You can prep this breakfast the day before and then bake it the morning of a holiday. Or, you can prep the whole dish on a weekend and enjoy it all week long.

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Ingredients

12 large eggs
½ cup milk or half & half
1 red bell pepper diced
1 green bell pepper diced
1 yellow onion diced
4 medium-sized gold potatoes (about 1 ½ - 2 cups worth) diced, or a bag of already prepared breakfast potatoes. *If using shredded, squeeze out all of the water first
1 lb pork sausage roll I use Bob Evans Original
16 oz. shredded cheddar cheese
2 tablespoon vegetable oil divided
salt and pepper to taste

Instructions

Prep: Grease a 9x13 casserole dish with butter or nonstick cooking spray. Dice onion and bell peppers. Chop potatoes into even bite-sized pieces. Set aside.
If cooking the same day: Preheat oven to 375 F.
Heat a large frying pan over medium-high heat with one tbsp. of oil.
Sauté onion and bell peppers until just about fork tender. Then, place it in the prepared casserole dish.
To the same pan, add another tbsp. of oil. Cook potatoes until browned and fork tender (about 10-12 minutes), stirring frequently to prevent burning. Then, place it in the casserole dish. Tip: If the potatoes are browning too quickly and aren't tender yet, turn the heat down to low and place a lid on the pan. Cook for 5 more minutes, or until fork tender.
To the same pan, add sausage. Cook the sausage, crumbling as you go, until browned and completely cooked through. Place in casserole dish.
Mix all of the ingredients in the casserole dish until evenly distributed. Smooth into an even layer.
Place the casserole dish in the fridge until ready to cook (can leave it overnight). If cooking right away, disregard this step.
When ready to cook: Preheat oven to 375 F. In a large mixing bowl; whisk eggs, milk or half & half, and salt and pepper until smooth. Pour evenly over the sausage-veggie mixture. Add shredded cheese to the top of the egg casserole.
Cover with foil and bake for 35 minutes, or until the edges have set. Remove foil and bake an additional 25-30 minutes, or until cooked through in the center. Test with a toothpick for doneness. You can also broil the last 5 minutes to encourage even more browning. Tip: All oven temperatures vary, so keep an eye on your casserole. If browning too much, you can cover it again with foil.
Enjoy within 3-4 days. Serve with your favorite sauce (ketchup, hot sauce, etc.)

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