In a skillet, brown steak in oil; transfer to a crockpot.
In the same skillet, sauté onion for 1 minute. Gradually add water, stirring to loosen browned bits from pan.
Add remaining ingredients; bring to a boil. Pour over the flank steak. Cover and cook on LOW for 7 to 8 hours or until the meat is tender.
Slice the meat; serve with onion and pan juices.
Servings: 4