Preheat the oven to 350°F (175°C).
In a large bowl, whisk the eggs until smooth.
Add the cottage cheese and mix until well combined.
Stir in diced red bell pepper, yellow onion, chopped spinach, garlic, Italian seasoning, kosher salt, and ground black pepper.
Fold in the shredded gruyere/gouda and cheddar cheeses.
Pour the mixture into a greased 9x13 inch baking dish and spread evenly.
Bake in the preheated oven for 35-40 minutes or until the egg bake is set and the top is lightly golden.
Remove from oven and let cool for 5 minutes before slicing.
Serve warm and enjoy your protein-packed breakfast casserole.