Tender oven baked ribs are coated with BBQ seasoning, wrapped with butter, and baked low and slow until they pull easily from the bone but still have some bite. Finish them with BBQ sauce at high heat for a sticky, caramelized glaze.
Prep the oven: Preheat the oven to 275°F. Line a sheet pan with foil for easier cleanup.
Check for the membrane: Turn the ribs bone-side up and check for a thin, shiny membrane covering the bones. If it's still attached, loosen one end with a butter knife, grip it with a paper towel, and pull it away. If the membrane has already been removed, skip this step.
Season the ribs: Pat the ribs dry, then spread the mustard over the top, bottom, and edges. Add the BBQ dry rub, pressing it onto the ribs until every side has a solid, even coating.
Wrap with butter: Place the ribs meat-side up on heavy-duty foil and arrange the sliced butter over the top. Wrap a large rack individually or smaller racks together if they fit comfortably. Seal the foil tightly. If you're using regular foil, double it up. If the foil doesn't close around the ribs, add another strip over the top and crimp the sides up and in to form a sealed packet.
Bake until tender: Bake the wrapped ribs at 275°F for 2½ hours. The ribs should be tender and pull easily from the bone while still having some bite. For larger ribs or softer ribs, continue baking for up to 30 minutes more.
Add the BBQ sauce: Increase the oven temperature to 425°F. Carefully open the foil, pour off the excess liquid, and brush the ribs with BBQ sauce.
Set the sauce: Bake uncovered for 10 to 12 minutes, or until the sauce is bubbling and sticking to the ribs.
Broil, if desired: For darker, stickier edges, broil for 2 to 4 minutes. Watch closely since the sauce can darken quickly.
Rest and serve: Rest the ribs for 10 minutes before slicing between the bones. Serve with additional BBQ sauce.
Notes
Rib size: Rib racks can vary quite a bit in size. Depending on what you find, 2¾ pounds may be one large rack or two smaller ones. This recipe also works well with up to about 3½ pounds of ribs.
Doneness: At 2½ hours, the ribs should pull easily from the bone but still have some bite. Larger ribs may need closer to 3 hours.
Store-bought rub: Some blends contain more salt, so use less than 8 tablespoons if needed. The BBQ sauce adds another layer of flavor.
Make ahead: Season the ribs up to 24 hours ahead and refrigerate until ready to bake.