Wipe the mushrooms clean and remove the stems. Set aside the 12 largest caps.
Finely chop the remaining mushrooms and stems (you can do this in the food processor). Set aside.
In a large skillet, heat the oil over medium-high heat.
When the oil is hot, add the sausage. Cook for about 5 minutes...breaking up the sausage with a wooden spoon as it cooks.
Add the green peppers, garlic and chopped mushrooms. Cook for another 10 minutes, until most of the moisture from the mushrooms have evaporated.
Add the bread crumbs and chicken stock.
Reduce the heat to medium and stir in the cheese and the cherry peppers.
Spread the mixture onto a platter and then place in the fridge to cool.
Pre-heat the oven to 400 F.
Stuff each of the mushroom caps with the sausage and pepper mixture and place in a large roasting or casserole dish.
Drizzle the stuffed mushrooms with olive oil.
Bake for 35 minutes...or until nicely browned on top, and the mushrooms are soft.
Transfer the mushrooms to a platter and and spoon the remaining pan juices over the top.
Garnish with finely chopped parsley.