Baby Back Ribs with Mixed Berry–Chipotle Glaze

Pat ribs dry. In bowl, mix chipotle chile powder, Old Bay seasoning, 1 teaspoon salt, 1/2 cup brown sugar, and 1 teaspoon garlic powder. Rub all over ribs. Tightly wrap in aluminum foil; refrigerate ribs at least 2 hours or overnight. Preheat oven to 350 degrees F. Place wrapped ribs in jelly-roll pan and bake 1 hour 30 minutes or until tender. Carefully unwrap; transfer 1/4 cup collected juices to measuring cup; discard remaining. In food processor, pulse berries, ketchup, vinegar, chiles, 1/4 teaspoon salt, and remaining 1/4 cup brown sugar, 1/2 teaspoon garlic powder, and meat juices until smooth. Press through fine-mesh sieve into medium bowl; discard seeds. In 4-quart saucepan, heat olive oil on medium-high. Add onion and cook 5 minutes or until soft, stirring occasionally. Add berry mixture, heat to boiling, then reduce heat and simmer 20 to 30 minutes or until reduced by about one-third (to about 2 cups). Prepare grill for direct grilling on medium-high. Set aside half of berry glaze for serving. Grill ribs 8 to 10 minutes or until glossy, basting with remaining glaze and turning over occasionally. Transfer to platter; garnish with berries. Serve with reserved glaze.