Wash the tomatoes. Cut tomatoes and mozzarella into slices. Wash basil, shake dry, pluck leaves. Dab meat dry and cut into strips. Fry in hot oil all around for 4-5 minutes.
Season with salt and pepper.
Mix mayonnaise, mustard and lemon juice. Season to taste with salt and pepper. Cut the bread into 4 pieces, then cut it and fill it with mozzarella, tomatoes, basil and meat. Spread mustard cream on top.