Add the eggs, cottage cheese, salt, and pepper to a blender and blend until smooth (about 15–30 seconds). This ensures a fluffy texture and removes any cottage cheese curds.
Heat a small nonstick skillet over medium-low heat and add butter or oil to lightly coat the surface.
Pour the blended egg mixture into the skillet, allowing it to spread evenly.
Let the mixture cook undisturbed for 1–2 minutes until the edges start to set.
Gently lift the edges with a spatula and tilt the pan so the uncooked egg flows underneath. Repeat this process until most of the mixture is cooked, about 7–8 minutes.
Sprinkle the chopped red bell pepper, red onion, and feta over one half of the omelette.
Carefully fold the omelette in half. Reduce heat to low, cover the skillet with a lid, and let it cook for an additional 3–4 minutes to soften the veggies.
Transfer the omelette to a plate and serve immediately. Enjoy!