1. Rinse ribs and pat dry. Rub spice mixture over both sides.
2. Line two 12- by 17-inch baking pans with foil. Set a rack in each and lightly coat with cooking oil spray. Set ribs, meaty side up, in a single layer on racks.
3. Bake in a 425° oven until ribs are lightly browned on top, 20 to 30 minutes. Turn each slab over and switch pan positions. Continue baking until ribs are browned, 20 to 30 minutes longer.
4. Brush generously with glaze. Continue baking, basting occasionally, until glaze is browned and bubbly, 6 to 12 minutes. Turn ribs over and brush generously with more glaze. Bake, basting occasionally, until glaze is browned and meat between ribs is no longer pink in the center (cut to test), 6 to 12 minutes longer.
5. Transfer ribs to a board. Let rest 5 minutes. Cut between ribs.
Chili-cumin rub. Mix 3 tablespoons chili powder, 3 tablespoons coarse salt, and 2 tablespoons cumin seeds.
Curry spice rub. Mix 3 tablespoons coarse salt, 3 tablespoons curry powder, 1 tablespoon ground ginger, and 1 tablespoon ground coriander.
Honey-lime-chipotle glaze. Mix 1 cup honey; 6 tablespoons lime juice; and 2 tablespoons minced canned chipotle chiles, Asian red chili paste, or hot chile flakes.
Apricot-mustard glaze. In a blender, whirl 1 1/3 cups apricot jam, 1/2 cup Dijon mustard, and 1/2 cup white wine vinegar until smooth.
Per serving with chili-cumin rub and honey-lime-chipotle glaze.