To sauté is to cook in a wide, shallow-sided pan over high heat using a small amount of butter or oil, or a combination of the two. Sautéeing chicken pieces gives you great flavor from the browning or caramelization of the skin with very little fat. That’s why I recommend buying and preparing chicken skin on; if you can’t buy it or you strongly prefer skinless chicken, sautéeing is still a fine approach. The outside of the meat will color a bit, but you just won’t get the big flavor boost or the browned bits useful for making a pan sauce.