Yankee Barbecue Beef
["6 Tbsp. butter, melted", "6 Tbsp. flour", "6 Tbsp. brown sugar", "3 Tbsp. mustard", "1 1/2 c. ketchup", "1 tsp. salt", "3 tsp. vinegar", "1 1/2 ??? water"]
["Add to shredded roast beef.", "Heat and serve."]
["butter", "flour", "brown sugar", "mustard", "ketchup", "salt", "vinegar", "water"]