- Combine hoisin sauce, ketchup, soy sauce, vinegar and 1-1/2 Tbsp. water. Remove 1/2 cup mixture; pour into small saucepan. Bring mixture just to boil, stirring constantly. Remove from heat and cool to room temperature.
- Meanwhile, place pork on rack of broiler pan; brush with half of remaining sauce mixture. Bake pork in 400ºF. oven 25 to 30 minutes, or until meat thermometer registers 155º, brushing with remaining sauce mixture after 15 minutes. Let pork stand 10 minutes.
- Pour cooled sauce into small serving bowl for dipping. Cut pork across grain into thin slices and serve with dipping sauce.