- 1/4 cup mild-flavored (light) molasses
- 3 tablespoons apple cider vinegar, divided
- 2 tablespoons Dijon mustard
- 2 tablespoons coarse-grained mustard
- 1 3/4-pound pork tenderloin
- Whisk molasses, 2 tablespoons vinegar, and both mustards in small bowl to blend. Place pork in heavy-duty resealable plastic bag. Pour marinade over. Seal tightly and refrigerate 4 hours.
- Prepare barbecue (medium-high heat). Drain marinade into heavy small saucepan. Sprinkle pork with salt and pepper. Grill pork until thermometer inserted into center registers 145°F, turning occasionally with tongs, about 20 minutes. Transfer pork to serving platter; let rest 5 minutes.
- Meanwhile, add 1 tablespoon vinegar to pan with marinade and boil until thickened to sauce consistency, about 1 minute.
- Cut pork crosswise on slight diagonal into 1/2-inch-thick slices. Arrange pork slices on platter; drizzle sauce over.