Clean and stem the mushrooms. Reserve about 10 stems and chop finely. Set aside.

Cook the bacon until crispy. Drain on paper towels. When dry, crumble finely. Set aside.

Place the bread in a food processor or blender and blend until crumbs are formed. Set aside.

In a medium-sized saute pan over medium heat melt 2 tablespoons of butter and 2 tablespoons of olive oil. Add the shallots, garlic, and reserved mushroom stems. Saute for about 5 minutes or until the vegetables become soft. Stir in the spinach, salt, and pepper and cook until the spinach is wilted.

Place the crab meat in a medium-sized bowl. Add the reserved bacon and the vegetable mixture.

To the same pan that you cooked the vegetables in, add the remaining 2 tablespoons of butter and melt. Add the reserved breadcrumbs and cook until the bread begins to brown, stirring constantly. Add the breadcrumbs to the crab mixture along with the cheese. Combine well.

Stuff the mushrooms with the crab mixture and place in a baking dish large enough to hold the mushrooms. Place about 1/2 cup of water in the bottom of the baking dish and drizzle the mushrooms with additional olive oil and sprinkle more cheese on top.

Bake at 375 degrees for 25-30 minutes or until the tops are browned and the mushrooms have softened.