Whisk molasses, 2 tablespoons vinegar, and both mustard's in small bowl to blend. Place pork in heavy-duty resealable plastic bag. Pour marinade over. Seal tightly and refrigerate 4 hours or the best is overnight.

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 140-145°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.

Serve on a bed of curry lime mashed butternut squash and haricot verts; grilled asparagus or grilled baby zucchini.