Preheat oven (electric cooker: 220 °C/circulating air: 200 °C/gas: see manufacturer). Clean, clean and slice the mushrooms. Wash and finely dice tomatoes. Wash parsley, shake dry, pluck off leaves and chop. Cut mozzarella into slices.
Heat 1 tablespoon of oil in a frying pan. Fry the bacon in it until crispy, take it out. Roast bread briefly in the bacon fat, then cover with cheese, bacon and mushrooms. Bake in the oven for about 5 minutes. Sprinkle with tomatoes and parsley. Season with pepper.