Bone and pound the chicken breasts. Dreddge with flour. Melt the butter in a baking pan. Coat chicken on all sides, turning skin side up if not boneless. Bake at 375 degrees, brushing with pan drippings for 30 minutes. Meanwhile, make the lemon baste, where you mix 1/3 cup lemon juice, minced onion, garlic and salt and pepper. Brush chicken with part of the baste, and bake, brushing with the remaining baster for 30 minutes longer or until done. Serve with rice and a vegetable.