Over medium high heat in a large hot pan saute the sausage while browning crumble the meat with a wooden spoon. Cook for 4 minutes. Blot the grease of the sausage with paper toweland discard. Add onions and peppers cook for 3 minutes.
Add diced mushroom stems and garlic sauteing and stirring for 3 minutes.
Add tomatoes and herbs simmer for 4 minutes.
Remove from heat and add mozzarella cheese mixing in to melt(this is the binder).
Fill stuffing the shrooms with filling mounding up nice and full.
Sprinkle with grated cheese.
Bake for 30 minutes.
Remove and place on a serving platter pour juices over the shrooms.