This Korean Spicy Chicken is supposed to have a kick.  That being said, you can control the heat of this Korean Chicken recipe by adding more or less of the reserved marinade (that becomes the dip/sauce) to the chicken after it is cooked.  This sauce is quite spicy so it will make your Korean Chicken that much spicier.  For less spicy chicken, don’t use the sauce. If you already know you don’t like spicy foods then start with just 2 tablespoons gochujang and use only one tablespoon brown sugar.