Barbecue Chicken Marinade

1 cube butter
1/3 c. Worcestershire sauce
3 TBS. vinegar
2 TBS. minced onion
1 ½ tsp. salt
½ tsp. ground pepper
2 TBS. lemon juice
½ tsp. dried mustard

Simmer 10-15 minutes. Marinate chicken breast 2 to 3 hours. Broil in oven or on grill.