Preparation: Trim all excess fat from roast. Place
potatoes and onion in bottom of crockpot. Make a smooth
paste of flour, mustard, chili sauce, Worcestershire
sauce, vinegar and sugar. Spread over top of roast (cut
roast in half, if necessary, to fit easily). Place roast
in crockpot on top of potatoes and onions. Cover and cook
on LOW setting for 10 to 12 hours (on HIGH setting for 5
to 6 hours). 4 to 6 servings (about 3 quarts).