Cut the steak into 4 to 6 pieces and pound each piece thinly with a mallet or the side of a cleaver. Place a slice of mozzarella cheese and 1 teaspoon of butter on each piece, then sprinkle each piece with Parmesan cheese, garlic, and raisins, and season with salt and pepper.
Roll each piece tightly and tie securely with string. Heat olive oil in a medium skillet over medium high heat. Saute each roll in the oil for 5 to 10 minutes, or until browned on all sides.
Drop these rolls into your favorite simmering tomato sauce for 1 1/2 hours, or until tender. Remove from sauce, cool slightly and remove the strings before serving.
