It gets its red color from different things. Most fast food take-out restaurants use fake red food coloring to make it look bright. But in this recipe, I go for something more natural. I add a bit of ketchup, which not only makes it red but also tastes better. Ketchup has sugar and vinegar, so it gives the sauce that classic red color and extra flavor. So, in this version, the red color comes from tasty ingredients, not fake stuff.