Heat the canola oil in a large nonstick skillet over a medium-high heat. Cook the onions and peppers until onions are softened and peppers are slightly charred, about 8 minutes. Add black beans and red pepper flakes and cook until warmed through, another 3 minutes. Season with salt and pepper and transfer to a dish.
Whisk together the eggs and egg whites then stir in the cheese. Spray the skillet with cooking spray, and reheat the skillet over a medium heat. Reduce heat to low and add eggs, scrambling until cooked through, about 3 minutes. Spread each tortilla with 1 tablespoon each sour cream (or yogurt) and salsa, then layer with 1/4 of the black bean mixture, 1/4 of the scrambled eggs, some diced tomato and 1/4 of the avocado. Season, to taste, with hot sauce. Roll up burrito-style and serve.