1 pepper, chopped
1 onion, chopped
1 stick celery, chopped
olive oil, as needed
4 large mushroom caps
1/2 cup tomato sauce
1. Preheat oven to 350 degrees F. Fry pepper, onion, and celery in a pan with oil.
2. Once browned, stir in the tomato sauce. Add mushroom caps to baking sheet.
3. Let simmer until hot, then pour the sauce into the mushrooms.
4. Place in oven for 5 minutes.