My dad made this every Christmas. It is a tradition. I'm told that it is mandatory.
Brown 1 lb butter and 2 large onions (chopped fine).
Add (4) 16 oz cans sourkraut (drained dry, chopped fine, reserve juice).
Cook over med heat until soukraut is browned. Add half of sourkraut juice and water to make 3/4 kettle.
Add 2 handfulls of raw rice. Simmer 1 hour. Add (4) 8 oz cans sliced mushrooms and juice. S&P to taste.