In scant amount of olive oil, cook mushrooms and onions until tender.
Rub fresh peppers with remaining oil.
Place on baking sheet.
Preheat oven to 350 degrees
In halved pepper, place one piece of provolone on the base.
Stuff each pepper equally with sliced roast beef, cooked seasoned mushrooms and onions. Add as much salt pepper and garlic powder that makes you comfortable. I just sprinkled a bit while the peppers were cooking.
Top with a spoonful of marinara
Top with another slice of cheese.
Bake 30 minutes until pepper is soft.
Rachel Ray precooks her peppers in a hot oven and then stuffs them to get z more tender pepper.