Preheat your oven to 350°. Prepare your muffin tin by spraying with nonstick spray. Set aside.
Preheat a fry pan over medium heat with olive oil. Once hot, add onion and pepper, cooking until softened, about 4-5 minutes. Add the spinach and scallions, cooking for an additional 1 minute. Set aside.
½ tbsp olive oil, ½ cup chopped red bell pepper, ½ cup chopped onion, 1 cup chopped spinach , 2 scallions
In a large bowl, whisk together the egg whites, cottage cheese, salt, pepper, and cheese. Add in the veggie mixture, mixing until fully combined.
16 oz egg whites, 5 oz cottage cheese, ½ tsp salt, ¼ tsp pepper, ½ cup shredded extra sharp cheddar cheese
Using a ¼ measuring cup, scoop the mixture evenly into the muffin pan.
Bake for 18-22 minutes or until muffins have puffed up and egg whites are completely cooked (not jiggly in the middle). The muffins will sink back down as they cool.
Muffins are best served warm. They can be stored in the fridge for up to 5 days and reheated in the microwave.