Herb Stuffed Grilled Chicken

4 (4oz) skinless, boneless chicken breasts
3 Tbsp butter or margarine
1/2 C chopped onion
1/2 tsp minced garlic
1/8 tsp dried marjoram
1 Tbsp fresh or 1 tsp dried parsley
1/8 tsp dried thyme
1/4 tsp salt
1/2 C bread crumbs
3 Tbsp melted butter or margarine
1 tsp grated lemon peel

Preheat grill. Soak wooden skewers or kitchen twine in shallow dish. Cut pocket in thickest side of each chicken breast and set aside. Melt butter in a medium skillet over medium heat. Add onion and garlic; saute until tender, about 5 minutes. Add marjoram, parsley, thyme, salt and bread crumbs to skillet; mix well. Spoon stuffing into chicken pockets; secure with wooden skewers or twine. Combine melted butter and lemon peel in small bowl for basting. Grill chicken, basting frequently, about 12 minutes per side.