In a large skillet, add the sausage over medium-high heat and begin to break down with a spatula.
Add shallots and broccoli rabe and continue to break apart the sausage while cooking for about 7 minutes.
Add in the garlic, chopped mushroom stems, and the salt, peppers, oregano, parsley, and wine and cook over medium-low. Continue cooking 10 minutes, breaking down the sausage and cooking the wine down.
Remove from heat and place the sausage mix into a mixing bowl.
Allow the sausage mixture to cool for about 10 minutes.
Add in the bread crumbs and parmesan cheese and mix well.
Place mushroom caps on a baking sheet and fill each mushroom cap with the sausage mixture. Caps should be overfilled and not level.