Philly Cheesesteak Stuffed Peppers

Slice peppers in half lengthwise, remove ribs and seeds. Slice onions and mushrooms. Saute over medium heat with butter, olive oil, minced garlic and a little salt and pepper. Sauté until onions and mushrooms are caramelized. About 25-30 minutes. Preheat oven 400 degrees. Slice roast beef into thin strips and add to the onion/mushroom mixture. Allow to cook 5-10 minutes. Line the inside of each pepper with a slice of provolone cheese. Fill each pepper with meat mixture until nearly overflowing. Top each pepper with another slice of provolone cheese. Bake for 15-20 minutes until the cheese on top is golden brown.