Mix together ground beef, cold cooked rice, onion, milk, salt and pepper to taste, garlic, egg and paprika; set aside.

Cut out the core of a large green cabbage. Place cabbage core side down on a plate in the microwave and cook for about 5 minutes.

Gently peel off several leaves intact.

Microwave again, in one minute increments, peeling off additional cabbage leaves each time.

Place a half cup mixture of beef on the inside lower/thick part of the cabbage leaf and roll the thick part over the meat. Fold over the side parts of the leaf and then roll up like a burrito.

Place 6 of these seam-side-down in the bottom of the crockpot, then top those with about half of the sauerkraut and half the tomato puree.

Make 6 more rolls and add to the crockpot.

Top that with the remaining sauerkraut, tomato puree and an additional cup of water.

Top cabbage rolls with a few extra cabbage leaves if you have any.

Cover and cook on low for 8-10 hours or until cabbage rolls are tender.