When the chicken hits the hot butter, you should hear a nice sizzle, and it will stick to the bottom of the pan. Leave them alone. After the first 2 – 3 minutes, use a pair of tongs to try to gently lift the chicken. If it still sticks, wait another 30 or so seconds and try again. When the chicken has crisped, it will easily release without any sticking. The whole process should take somewhere between 3 – 5 minutes, depending on the heat of your pan.