Gather the ingredients.

Preheat a gas grill for high heat, or arrange charcoal briquettes on one side of the barbeque. Lightly oil the grate.

Combine cumin, chili powder, paprika, salt, and pepper in a small jar; close the lid and shake to mix.

Trim the membrane sheath from the back of each rack. Run a small, sharp knife between the membrane and each rib, and snip off the membrane as much as possible.

Sprinkle the rub onto both sides of ribs as desired. Do not thoroughly rub spices into ribs to prevent them from becoming too dark and spicy.

Place aluminum foil on the lower rack to capture drippings and prevent flare-ups. Lay ribs on the top rack of the grill. Reduce gas heat to low and close the lid; cook ribs, undisturbed, until meat pulls away easily from the bone, about 1 hour.

Brush ribs with barbecue sauce, and grill for an additional 5 minutes.