01 - Preheat oven to 375°F. Grease a 9x9-inch baking dish with olive oil or nonstick cooking spray, ensuring even coverage on all sides and the bottom.
02 - In a large mixing bowl, whisk together the eggs and cottage cheese until smooth and fully incorporated with no lumps remaining.
03 - Stir in the shredded chicken or turkey sausage, cheddar cheese, spinach, bell peppers, red onion, salt, black pepper, garlic powder, and smoked paprika. Mix until all ingredients are evenly distributed throughout the egg mixture.
04 - Pour the egg mixture into the prepared baking dish, spreading it into an even layer using a spatula.
05 - Bake for 35 minutes, or until the center is fully set and no longer jiggles, and the top is lightly golden. A knife inserted into the center should come out clean.
06 - Remove from the oven and allow the casserole to rest for 5 minutes before slicing into 6 equal portions. Serve warm.