In a Dutch oven over medium heat, melt butter. Stir in flour until smooth. Add the next 10 ingredients, bring to a boil. Add roast. Reduce heat; cover and simmer for 3 hours or until meat is very tender. Remove meat; shred with two forks or a pastry blender. Skim fat from cooking juices; return meat to juices and heat through. Served with slotted spoon on buns.
Nutrional Analysis: One 3/4-cup serving(prepared with margarine and no-salt added ketchup and without salt; calculated without bun) 245 calories; 141 mg sodium; 80 mg cholesterol; 5 gm carbohtdrate; 29 gm protein; 5 gm fat.