The best way to cook chicken for tacos is to use an outdoor grill. It is great on either a charcoal grill or a gas grill. For juicy chicken and nice grill marks start with a hot grill between medium heat and high heat, leaving some of the surface area without any heat for indirect cooking. Start by placing the pieces chicken on the hot side of the grill. Cook for 4-5 minutes a side. Then move to the indirect side of the grill. Allow it to finish cooking until a meat thermometer registers the internal temperature at 165º. Follow the same procedure for cooking skirt steak. Remove when meat is done to your likeness