Slow-cooked cabbage rolls w/tomato sauce

Ingredients

• 12 leaves cabbage
• 1 cup. cooked white rice
• 1 egg, beaten
• 1/4 cup. milk
• 1/4 cup. vidalia onion
• 1 libra. extra-lean ground beef
• 1-1/4 teaspoon . kosher salt
• 1-1/4 teaspoon . lemon black pepper
• 1 (8 ounce) can tomato sauce
• 1 tablepsoon. brown sugar
• 1 tablepsoon. lemon juice
• 1 teaspoon . Worcestershire sauce