2 lbs. beef
1 pkg. onion soup mix
2 (4 oz.) cans whole mushrooms
2 cans Cream of Mushroom soup
1/2 c. red wine vinegar

Combine all ingredients in a 2 quart casserole dish, cover. Bake at 300 degrees for 3 hours. Don't peek until done. Serve over noodles or rice. Can be cooked in slow cooker.