"Philly" Stuffed Mushrooms - cooking recipe

Ingredients

2 lb. medium mushrooms
6 Tbsp. margarine
1 (8 oz.) cream cheese, softened
1/2 c. (2 oz.) crumbled Blue cheese
2 Tbsp. chopped onion

Preparation

Remove mushroom stems.
Chop enough stems to measure 1/2 cup. Cook half of mushroom caps in 3 tablespoons of margarine over medium heat for 5 minutes.
Drain.
Repeat with remaining mushroom caps and margarine.