Heat oven to 350 degrees F. Line a broiler-pan bottom with foil.
Whisk Dry Rub ingredients in a small bowl; rub on both sides of ribs. transfer to prepared broiler pan rack; cover tightly with heavy-duty foil. Roast ribs 1 1/2 hours until meat between ribs is fork tender
Mopping Sauce: Combine 3 ingredients in a 2 qt sauce pan; bring to a boil. Reduce heat to low and simmer 10 mins until sauce has reduced slightly and thickened; cool.
Bring grill to medium high heat. grill ribs, mopping them with sauce and turning them till slightly charred and glazed (10-12 mins).
Transfer ribs to cutting board. Cut into single or double rib portions.