In 10 inch skillet fry bacon until crispy. Remove from skillet. Add flank steak to drippings, cook until meat juices have evaporated. Add chopped onion, and cook until onions are translucent. Add tomato sauce, worcestershire sauce, and tobasco sauce, crumble bacon and add to mixture. let simmer for at least 30 minute. Secret: the longer is simmers the better it is. Right before serving stir in sour cream.
I like this best served over cooked noodles, but it is great by itself