Cheesy Stuffed Mushrooms w/ Herbs

4 large flat mushrooms
1 slice white bread
1/4 cup cheddar cheese
2 tablespoons butter
1 tablespoon fresh thyme, finely chopped
1 tablespoon fresh oregano, finely chopped
1 tablespoon fresh rosemary, finely chopped
1 clove garlic
salt and freshly ground black pepper
olive oil

Wash mushrooms and cut off stems. Combine bread, mushroom stems, thyme, oregano, rosemary, garlic, salt and pepper in a food processor and blend until evenly mixed. Don't over process. Brush tops of mushroom with olive oil and place 1/2 tablespoon of butter inside. Place on hot grill for about 4 minutes. Remove from grill and stuff with breadcrumb mixture. Return to grill and cook an additional 4 minutes.