Warm tortillas according to directions on package. In a small saucepan, saute onions and peppers until soft. Add salsa on low until heated through. Meanwhile, whisk egg substitute and milk in a small bowl. Cook in a nonstick skillet over medium heat, gently lifting the setting egg substitute mixture to allow the rest of the liquid to cook. When eggs are cooked through, though still moist, remove from heat and divide into four. Spread heated salsa on warmed tortillas, followed by one-fourth of the egg substitute. Sprinkle with cheese, then roll burrito style.