Heat oven to 350 F. In 10 inch skillet, melt 3 tablespoons butter over medium-high heat. Add onions and apple; cook and stir until tender. Stir in remaining stuffing ingredients. In ungreased 9x13 in pan, spread stuffing.
Salt and pepper chicken breast. Place breasts over stuffing. In 1 quart saucepan, melt jelly with 2 tablespoons butter over low heat; brush over chicken.
Bake uncovered 1 hour to 1 hour 15 minutes or until chicken is fork-tender and juice is clear when thickest part is reaches 180 F.