This was a big hit and so easy.
from Simply in Season (of course!)
2 lbs stewing beef, cut in 1 inch cubes
Place in crockpot.
1/3 c water
1/2 c ketchup
2 T vinegar
2T Worcestershire sauce
1 T brown sugar
1 t each salt, paprika, chili powder
Mix together and pour on top of beef and onions.
Cook on low in crockpot until beef is tender and easily shredded with two forks. Cook with the lid OFF for the last hour to reduce liquid. Mine took about a total for 5 hours.