Dry wipe mushrooms, remove stems.
Saute onions and pepper in butter till soft.
Dice crab and shred with hands.
Mix all ingredients together EXCEPT 1 cup cheese and olive oil.
Stuff caps and place in greased pan.
Sprinkle with cheese, drizzle with olive oil.
Bake at 400 for 25-30 mins. Tops should be browned.