Combine butter and garlic in an 8-inch square baking dish.
Flatten chicken with a meat mallet; fold envelope fashion, and roll in breadcrumbs.
Place chicken in baking dish, turning to coat well. Bake at 350° for 30 minutes, basting occasionally. Add lemon juice; bake an additional 15 minutes or until tender. Transfer chicken to individual serving plates. Garnish with lemon and parsley.