Combine beer, TABASCO® Chipotle Sauce, onion, molasses and salt in a gallon-size zipper bag; mix until salt dissolves. Cut the racks in half and add to the bag. Seal the zipper, leaving about an inch open; push on bag to release any trapped air through opening, and close zipper completely. Massage liquid gently into meat and refrigerate for 6 to 12 hours.
Brush grill grate and coat with oil. Put ribs on grill away from the heat; cover grill and cook until an instant read thermometer inserted into thickest part of ribs registers about 155°F, about 1 hour. If your grill has a temperature gauge it should stay between 350°F and 375°F.
Brush ribs with half of the Chipotle Grilling Sauce, turn, cover and cook for 3 minutes. Brush with remaining sauce, turn, cover, and cook for another 3 minutes.
Remove ribs to a large serving platter, cut into 1- or 2-rib sections.
Makes 4 servings.
Recipe by Dave Joachim and Andrew Schloss.