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Spinach and Feta Egg White Cups

These egg white cups combine potatoes, mushrooms, spinach, and feta with egg whites to make a nutrient dense breakfast that’s great reheated and perfectly portable. As you’d expect from my blog, this is a super simple recipe. You’ll only need five simple ingredients, excluding spices, to make these egg white cups.

These egg white cups are loaded with veggies but require minimal prep thanks to simple ingredient selection. They're great as a breakfast meal prep recipe!

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Ingredients for These Egg White Cups

To make things as simple as possible, the recipe calls for convenience forms of every ingredient. I’ll briefly cover the ones you might have questions about modifying.


You may raise an eyebrow when you come across canned potatoes in the recipe card below. I first used canned potatoes in my loaded air fried chicken and potatoes recipe and have been hooked since. They’re perfect for quick recipes because you don’t need to do any chopping or cooking to soften the potatoes. For another recipe to make with canned potatoes, check out my chorizo con papas breakfast quesadillas.

potato mushroom spinach and feta egg white cups step 1

That said, if you’d rather use fresh potatoes, peel and finely dice them to cook for a few minutes until soft before adding the mushrooms. If you didn’t want to peel the potatoes, you could use baby gold or Dutch yellow potatoes like I used to make breakfast potatoes in the air fryer. They’re softer and creamier than russet potatoes.


The recipe calls for frozen or canned chopped spinach for convenience (and because, Popeye).

If you wanted to use fresh, you’ll need to cook the spinach over medium heat until it begins to wilt. Then remove the spinach from the heat to cool and chop.

potato mushroom spinach and feta egg white cups step 2


This is the only fresh ingredient the recipe calls for, but you could certainly use a canned version of sliced mushrooms if you’d rather. If you go this route, be sure to fully dry the mushrooms before adding since the canned versions retain even more moisture.


Liquid egg whites are just so darn easy for these types of recipes, and it would be a shame to waste 9 egg yolks. That said, if you wanted to use whole eggs, that would work great.

A large egg usually weighs around 70-80 grams. So, to replace the egg whites with whole eggs you could whisk 5-6 eggs together.

potato mushroom spinach and feta egg white cups 1

Final Notes for Your Egg White Cups

I would highly recommend tasting the potato, mushroom, and spinach mixture before going in the muffin tin to assess the level of seasoning. The feta cheese will add some saltiness and slight flavor but if your veggies are bland before going in, your egg white cups may be lacking in the flavor department.

Okie doke, that’s all I have for you. You’ll find the full recipe card below.

If you make these egg white cups, I wanna see ’em. Take a photo and tag me on Instagram @mason_woodruff or join my free Facebook group and share it with the Proton Party.

Spinach and Feta Egg White Cups with Potatoes and Mushrooms

Spinach and Feta Egg White Cups with Potatoes and Mushrooms

Yield: 12 egg white cups
Prep Time: 10 minutes
Cook Time: 20 minutes
Total Time: 30 minutes

A simple recipe for egg white cups loaded with veggies. 


  • 1 1/2 C (396g) Liquid Egg Whites, or the whites of 8-9 eggs
  • 15 oz can Diced Potatoes, drained
  • 1/2 C (115g) Chopped Spinach, canned or thawed from frozen and drained
  • 1 1/2 C (100g) White Mushrooms, roughly chopped
  • 1/2 C (56g) Crumbled Feta Cheese
  • 1/8 tsp Salt and Pepper
  • 1/8 tsp Cayenne Pepper, to taste (optional)


  1. Preheat an oven to 350F and spray a 12-muffin tin with nonstick cooking spray. I used a silicone muffin mold on top of a baking sheet.
  2. Add the drained potatoes and mushrooms to a large skillet over medium-high heat. Sprinkle the salt and peppers over the mixture. Cook until the mushrooms begin to brown slightly and the potatoes begin to crisp around the edges, about 6-8 minutes. (If you'd like crispier potatoes, cook them a few minutes on their own before adding the mushrooms.) potato mushroom spinach and feta egg white cups step 1
  3. Add the spinach and stir well, spreading out the spinach as evenly as possible. Reduce the heat and cook until everything is evenly mixed and no moisture remains, about 4-5 minutes.  potato mushroom spinach and feta egg white cups step 2
  4. Spoon the mixture into the muffin tin as evenly as possible. potato mushroom spinach and feta egg white cups step 3
  5. Crumble the feta cheese and sprinkle it over the spinach mixture. potato mushroom spinach and feta egg white cups step 4
  6. Pour the egg whites over the mixture. If you're using liquid egg whites from a carton, you may want to go straight from the carton for easy pouring. You can place the carton on a food scale and zero out the scale to see how much you're pouring into each slot. (The amount may vary based on the size of your muffin tin.) potato mushroom spinach and feta egg white cups step 5
  7. Bake for 20-23 minutes or until the egg white cups are fully cooked through. Let the cups cool for a few minutes before removing from the muffin tin. Refrigerate leftover egg cups for 2-3 days. 


  • Each egg cup has 1 Smart Point.
  • If you use canned mushrooms, be sure to drain well and remove as much moisture as possible.
  • For fresh potatoes, dice and cook a few minutes before adding the mushrooms. 
  • For fresh spinach, cook the spinach on its own until the spinach begins to wilt. Remove from the heat to cool and chop. Add the cooked spinach at the same step in the recipe. 
  • Taste the veggies before adding to the muffin tin/mold to assess your level of seasoning. 
  • To substitute whole eggs for egg whites, whisk together 5-6 large eggs. 
Nutrition Information:
Yield: 12 egg white cups Serving Size: 1 egg white cup
Amount Per Serving: Calories: 50Total Fat: 1gCarbohydrates: 4.7gProtein: 5.3g

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More Healthy Breakfast Recipes You Might Like

If you’re looking for something with a bit more volume, my southwest sweet potato breakfast hash is super filling and loaded with veggies as well.

healthy southwest sweet potato breakfast hash recipe

And if you’re looking for a breakfast to feed a crowd, my egg and chorizo breakfast casserole is a reader favorite.

egg and chorizo breakfast casserole

Amanda Cosmides

Wednesday 15th of April 2020

Subbing for Celiac

No subbing needed here! I still have these in my fridge and I absolutely LOVE popping one or two in the microwave in the morning for a filling part of breakfast! A little bit of ketchup too - perfection. For my egg white bites I added 1/2 cup of cottage cheese to the mix to try to get them to a consistency similar to that of the Starbucks red pepper egg white bites. I used a whisk attachment on my Kitchen Aid and tried my best to whisk the egg whites into the cottage cheese. It didn't work super well - I still had some cottage cheese clumps in the end, but they still taste delicious and I don't have any issue with textures so they're all good for me! I'm still on a quest to figure out how to get my egg white bites to resemble the Starbucks ones. I don't have an instant pot - I think that might be the key but if anyone has any suggestions let me know!


Tuesday 26th of November 2019

I make these for weekday breakfasts to grab and take with me to work! I really like them too because I know I'm getting in veggies at breakfast, which I sometimes struggle with (especially on work mornings). I usually do 300 g of egg whites and 2-3 whole eggs and I also do onions (frozen usually because easy duh!) because I do not care for mushrooms. Plus, I don't have a silicone muffin pan so I cook it in a regular pan and cut into squares. Pop them in containers or wrap in foil and they're easy to grab on my way to work! Yummmm.


Monday 25th of November 2019

These are my go to meal prep breakfast. All my coworkers ask me about them. I’ve had to send the recipe to several people because they say that they look and smell so good. I’ve made a double batch and they’ve stayed good in the fridge all week. I’ve also used half a can of potatoes just to cut out some of the carbs and they’ve still come out really good. I do use a ton of seasoning on the potatoes when I cook them just to add some more flavor. Overall, a definite favorite!

Andrea Fletcher

Monday 25th of November 2019

I subbed canned potatoes for the pre-chopped cubed potatoes in the bag. I love feta and spinach together so I didn't change anything other than the addition of turkey sausage. Due to the extra ingredient I did end up with a few more egg cups than the original recipe. If you do not already have them, I highly recommend silicone baking cups/trays when baking egg cups or you will spend days scrubbing your metal tins. These reheat really well in the microwave. I like to top with a tiny bit of Sriracha just for a little extra kick.


Monday 25th of November 2019

This first time I made these I ate them nonstop for two weeks! I used fresh potatoes, substituted feta for blue cheese, and totally omitted the mushrooms. These keep well in the fridge or freezer and heat back up perfectly each time.

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