4 large green bell peppers, cut in half from stem to bottom with stem and seeds removed

8 slices provolone or gouda cheese

1 pound deli sliced roast beef, cut into strips

1 pound mushrooms, sliced

1 large onion, sliced

3 tablespoons butter

1 salt to taste

Preheat oven to 350. Prepare peppers and put in oven.
Meanwhile, in a large pan, combine onion, mushrooms and butter. Cook over medium heat until onions and mushrooms are tender.
Drain juices, if needed, and add salt and roast beef.
Stir well and remove from heat.
Remove peppers from oven, add cheese to bottom, fill with mixture, then top with addi