Heat the butter or oil in a skillet over medium-high heat. Add the bell pepper and tomato and cook, stirring frequently, for 4-5 minutes.
Meanwhile, crack the eggs into a cup. With a fork, whisk in the paprika, chili powder, garlic powder, and salt. Pour the egg mixture into a nonstick, small skillet on medium-low heat. Top with the cooked bell pepper and tomatoes, and cheddar cheese.
Continue to cook, without stirring, until you can flip one side over, creating a half-moon omelette. Remove from heat and top with the cilantro and sour cream.