Fill 5- to 6-quart Dutch oven half full of water. Heat to boiling. Place whole cabbage in water, core side down. Cover; cook 2 to 3 minutes, turning over once, or until leaves can be removed from head. With slotted spoon remove cabbage from water. With tongs, carefully remove 6 leaves from head. Save remaining head of cabbage for later use. Shave or trim part of the thick rib from each leaf. Return leaves to water; cook 2 to 3 minutes or until wilted.
In medium bowl, mix ground beef, uncooked rice, 1/3 cup milk, the egg, Worcestershire sauce, 1/4 teaspoon of the salt and 1/8 teaspoon of the pepper. Spoon about 1/3 cup of the ground beef mixture on thick end of each cabbage leaf. Roll up, tucking sides in. Place filled cabbage leaves in 12-inch skillet, seam side down. Add broth and caraway seed. Cover; heat to boiling. Reduce heat; simmer 25 to 30 minutes or until thermometer inserted in center of ground beef mixture reads 160°F.
With slotted spoon, place cabbage rolls on serving platter; cover to keep warm. In small bowl, mix 1/2 cup milk, the sour cream, flour, remaining 1/4 teaspoon salt and 1/8 teaspoon pepper with wire whisk. Pour into skillet. Cook and stir over medium heat until thick and bubbly. Serve sauce over cabbage rolls; sprinkle with bacon.