1Heat oil,add butter till melted,add mushrooms,salt and pepper to taste,cook until soft. Add garlic and cook 1-2 minutes. Remove from heat, add parsley and Parmesan cheese.
Split loaf of bread lengthwise. Spread mushrooms and butter mixture on each half. Add tomato slices down length of bread,season tomatoes with salt and pepper,top with mozzarella slices. Heat under broiler until bread is toasted and cheese is melted.