Cut the top of the whole bread, cut out the filling, then slice the butter thinly inside and place it on top
Slice the mushrooms in shape, and slice the onions into squares smaller than the size of the cut mushrooms.
Mix ingredients equivalent to a meatball to make a meatball about 5cm in size, roll it in a pan, cook it, add the mushrooms and onions, stir-fry them together, then add tomato sauce and stir-fry them
Put 3 in 1 loaf of bread, add pizza cheese, and bake in an oven at 200℃ for about 5 minutes.