Finely grate enough peel from lemon to measure 2 tsp. Cut lemon in half; squeeze juice from one half. Set aside. slice one garlic clove; place sliced garlic, 2 tsp. basil and the remaining lemon half in the cavity of the chicken.
Place chicken breast side up, in shallow roasting pan; rub with reserved lemon juice. Mince remaining garlic; combine with butter and reserved lemon peel. Brush mixture over chicken. Sprinkle with salt, pepper and remaining basil.
Bake uncovered at 375°F for 1 1/2 hours or until a meat thermometer reads 180°F. Let stand for 15 min before carving.