Mushroom London Broil Grill - cooking recipe

Ingredients

1 (3 lb. 1 1/2-inch) London broil
4 Tbsp. oil
4 Tbsp. dry sherry
1 small minced onion
2 Tbsp. butter
1/4 tsp. pepper
1 Tbsp. celery salt
1/2 tsp. dry mustard
2 Tbsp. vinegar
1 lb. chopped fresh mushrooms
2 Tbsp. melted butter

Preparation

Combine oil, sherry, pepper, celery salt, dry mustard and vinegar.
Pierce holes in steak with a fork.
Marinate steak and mixture in refrigerator overnight.