Easy Peasy Bacon N' Cheese Stuffed Mushrooms

Oh goodness its been way too long since ive made these!
WARNING: Oh they are delicious!

Easy Peasy Bacon N' Cheese Stuffed Mushrooms
Ingredients:
18 to 20 medium mushrooms
8 slices bacon
3 tbsp. mayonnaise
(1/2 c.) shredded Cheddar cheese

Heat oven to 350 degrees. Wash and drain mushrooms, remove stems. Finely chop stems. In medium skillet, cook bacon until crisp. Remove bacon, drain on paper towel. Crumble bacon, set aside. In small bowl, blend bacon, mushroom stems, onion, mayonnaise and cheese. Fill mushroom caps with stuffing mixture. Place mushrooms on ungreased pan. Bake at 350 degrees for 15 to 20 minutes until hot and cheese is melted. 18 to 20 appetizers.