Heat oven to 425 degrees. Season pork tenderloin with salt and pepper; roast in shallow roasting pan for 20-30 minutes, until internal temperature, reads 155-160 degrees. Pour glaze evenly over tenderloins during last 10 minutes of roasting time. Serve tenderloins thinly sliced.
Glaze: Drain cherries, reserving juice. Add enough cheery-flavored juice to make one cup. In a small bowl, stir cornstarch into 2 tbsp. juice. In small saucepan, combine cornstarch mixture with remaining juice, cherries, brown sugar and cranberries. Cook, stirring, until mixture boils and thickens; stir in mustard.