Heat oven to 400 degrees.
Place chicken, skin side down, in single layer in a shallow baking pan lined with foil.
Mix all ingredients except mushrooms and butter.
Pour orange sauce over pieces of chicken.
Bake 45 minutes, basting occasionally.
Turn over and bake 15 to 25 minutes longer.
Meanwhile, saute mushrooms in butter.
To serve, spoon mushrooms and any remaining sauce over hot chicken.