01 - Preheat the oven to 350°F (175°C). Lightly grease a 6-cup silicone muffin pan or line with paper liners.
02 - In a medium mixing bowl, whisk together egg whites and cottage cheese until smooth and frothy.
03 - Fold in shredded cheddar cheese, chopped spinach, diced red bell pepper, sliced green onions, salt, black pepper, and smoked paprika if desired.
04 - Divide the mixture evenly among the prepared muffin pan cups, filling each approximately three-quarters full.
05 - Bake in the preheated oven for 18 to 20 minutes, or until the centers are just set and the tops are lightly golden.
06 - Cool for 5 minutes before gently removing from the pan. Serve warm or refrigerate for later use.