Put rice in a small pot and add just enough water to cover. Cook only until water has been absorbed by rice.

Mix ground beef, onion, rice, egg, salt and pepper and set aside.

Core out the bottom of the cabbage heads.
Add 1 head at a time to boiling water, pulling leaves off head and cook until soft.
Remove thick portion of cabbage leaf with a paring knife. Chop the remaining small cabbage heads, line the bottom of the roaster and alternate between layers of cabbage rolls.
Please filling in the scoop of the cabbage leaf, folding one side over the filling and rolling to the end, then push the opposite leaf side into the roll. Pour 1/3 of the juices, sauce, sauerkraut and chopped cabbage over each layer of cabbage rolls.

Bake at 350 for 5 hours.
Fills an 18 quart roaster