Preheat oven to 375°F.
Cook the cabbage leaves in a saucepan of simmering water for about 5 to 8 minutes or until soft enough to work with. Remove leaves; cool under running water. Drain.
Melt butter in small saucepan over medium-low heat. Whisk in flour until smooth paste. Stir in Bloody Mary mix, broth, sugar, vinegar, salt and pepper; cook, whisking, until thickened, about 2 minutes.
Combine beef mix, bread and 4 tablespoons of thickened tomato sauce in medium-size bowl.
Spoon meat mixture into center of each leaf, dividing equally. Fold leaves over to form envelope-like package. Place, seam side down, in 13 x 9 x 2-inch baking dish. Cover with remaining tomato sauce. Cover with aluminum foil.
Bake in 375°F oven for 35 to 40 minutes or until meat is fully cooked.