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Rise and shine with this Egg White Breakfast Casserole! This balanced breakfast is packed with protein that will keep you full all morning. It’s easy to put together and can be made ahead of time so when you wake up in the morning, all you need to do is grab your breakfast and go!
When I started really diving into nutrition and understanding it, I finally understood why they say breakfast is the most important meal of the day. It really does kickstart your body and energy and sets you up for a successful day of eating. I hardly ever skip breakfast anymore and one of the reasons I used to skip it was because I just didn’t know what to make that was fast and easy. This egg white breakfast casserole literally takes all the guesswork out and if you’re usually in a rush in the mornings, like I am, then this high protein breakfast casserole is for you!
Why You’ll Love This
- Meal prep greatness. I absolutely love making this on my meal prep Sundays. It’s really easy to put together and you can put it together first while you do other meal prepping because majority of the time, this casserole is just baking. It really sets you up for the week!
- Macro friendly breakfast casserole. If you’re counting macros, you’ll see that this egg white breakfast casserole has great macros and really helps you with that protein goal!
- Mornings made easier. Since this is made ahead of time, you don’t have to worry about making breakfast every morning. It’s just literally grab-and-go.
- Fuel for your day. Loaded with protein and other nutritious ingredients, this egg white casserole will definitely fuel you up for the day. It helps curb the hunger and keeps you full until at least lunchtime!
Ingredients You’ll Need
The beauty of this egg white breakfast casserole is its short ingredient list. Make sure to scroll down to view the full recipe for exact measurements.
- Smoked sausage
- Onions
- Shredded hashbrowns/potatoes – frozen is easiest and best, but I also have used Simply Potatoes which is like a “fresh” kind.
- Egg whites
- Heavy cream
- Garlic powder
- Salt and pepper
- Shredded cheese
How To Make Egg White Breakfast Casserole
Here is a general overview of the steps involved to make this egg white breakfast bake. Be sure to scroll to the bottom of this post for the full recipe.
Preheat the oven and prepare a baking dish. Set the oven to 350 degrees F and generously spray a 9×13 inch baking dish with cooking spray. Set aside.
Brown the sausage and cook the onions. In a medium skillet, brown the sausage on both sides then add the diced onions and cook until tender. Remove from heat and let cool for 10 minutes.
Put the casserole together. In a large bowl, add the shredded potatoes then pour in the liquid. Mix together. Add the sausage, onions, seasonings, and cheese. Stir to evenly incorporate.
Bake. Pour the mixture into the prepared baking sheet and bake covered (with foil) for 1 hour, or until the center is no longer jiggly. Remove foil 15 minutes prior to finishing to brown the top a little bit.
Let cool and slice. Allow casserole to cool for at least 30 minutes before slicing and storing into containers.
Substitutions and Variations
You can easily customize this breakfast casserole with your favorite ingredients. Add some veggies like bell peppers or spinach for an extra boost of veggies to start the day or switch it up with chicken sausage or turkey sausage. There are so many possibilities!
Tips for Success
Starting your day with breakfast is a guaranteed way to fuel your body. I’ve got some tips and tricks to help you make this the best egg white breakfast casserole!
- Use liquid egg whites. I didn’t think you would break eggs individually to get the egg whites but I thought I’d make doubly sure that you aren’t doing that! They sell big containers of them and Costco always has a great deal.
- Break or cut up sausage into smaller pieces. I prefer a bite of sausage in every bite so to ensure that, you’ll want to make sure you break up the sausage or cut it up into smaller pieces.
- Cover the casserole. You definitely want to cover the casserole while it bakes. The foil acts like a tent and keeps all the steam in to help cook it faster. I did it once without the foil and not only did it dry out the breakfast casserole, it took almost two hours to bake. Yeah, never making that mistake again!!
Storage and Reheating Instructions
- For meal prep: allow the casserole to cool before slicing and storing into containers. We divide the slices into glass containers and put them in the refrigerator to grab and go in the morning. You may also wrap them in plastic wrap or foil, but glass containers with a lid make for the easiest way to transport.
- To reheat: every time I reheat this egg white breakfast casserole, I put a damp paper towel on top and put it in the microwave for 45 seconds to reheat. The damp paper towel creates a steam/moist environment to prevent the slices from drying out too much.
- To freeze: you can freeze this for up to three months. Allow to cool completely before you put them into freezer-safe containers or bags. Thaw and reheat as normal.
What to Serve with Egg White Breakfast Bake
This egg white breakfast casserole is a complete meal in and of itself but if you really want to be extra filled up, here are some great dishes to serve along side this breakfast casserole:
- Coconut Chia Seed Pudding with Berries and Granola
- Apple Pie Overnight Oats
- Iced Brown Sugar Oatmilk Shaken Espresso Latte
- Pitaya Smoothie Bowl
Egg White Breakfast Casserole
Equipment
Ingredients
- 10 ounces (284 g) smoked sausage or breakfast sausage, diced
- 1 medium onion, finely diced
- 20 ounces (567 g) frozen shredded hashbrowns
- 3 cups (729 g) liquid egg whites
- ½ cup (118 ml) heavy cream, or milk
- 1 teaspoon garlic powder
- 1 teaspoon kosher salt
- ½ teaspoon ground black pepper
- 1 ½ cup (168 g) shredded cheese
Instructions
- Preheat oven to 350 °F (177 °C) and generously spray a 9×13 inch baking dish with cooking spray. Set aside.
- In a skillet, brown sausage on both sides or break into smaller pieces (if using fresh sausage). Add the onions and cook until tender, about 5 minutes. Remove from heat and allow to cool for 10 minutes.
- In the meantime, add hashbrowns, egg whites, and heavy cream to a large bowl and mix together.
- Once the sausage and onion mixture has cooled, add to the bowl of the potatoes. Season with garlic powder, salt, and pepper. Then add the cheese and stir to incorporate.
- Pour mixture into prepared baking pan then cover with foil. Bake for 1 hour, or longer, depending.
- Remove foil 15 minutes prior to finishing baking.
- Remove from oven and let casserole cool for 30 minutes before slicing, serving, and/or storing.
I also made this for meal prep this week and it turned out great! We also added some spinach for an extra veg. This was a great variation from our usual “egg bake” – the potatoes make it a lot more filling!
I made this last week as meal prep for the week and it’s great for breakfasts!
I made a couple changes based on what I had, which made it like a Denver omelette, kind of. I used a package of smoked ham deli meat in place of sausage, and added a chopped bell pepper in with the onions. I also couldn’t find shredded hash browns so I peeled a potato, twisted out the water, and subbed that in (~1.5 cups total).
This has been a great breakfast or after work snack. I think I cut it into 10 pieces instead of 12 and they’re super filling, and tasty. I don’t even love eggs but really appreciate the high protein breakfast. I’ll definitely make again, and love how customizable it is!
I’m so making this next week! Breakfast is the hardest for me to plan for during the work week. And you’re right eating breakfast does make a difference.
Just made this and it’s amazing! Also awesome knowing I have breakfast taken care of for the week too.