In a mixing bowl, combine brown sugar, salt, smoked paprika, garlic powder, onion powder, ground cumin, dried oregano, ground mustard, and cayenne pepper.

Remove the membrane from the back of the Baby Back Ribs, rinse under cold water, and pat dry.

Coat the ribs with half of the spice rub mixture, massaging it into the meat and letting it rest for 15 minutes before applying the remaining rub.

Preheat your smoker to 225°F (107°C) and lay the seasoned ribs onto the grates. Smoke for about 2 hours.

Wrap the ribs in aluminum foil and return to the smoker for an additional 1½ hours.

Unwrap the ribs and brush with BBQ sauce. Smoke for another hour to caramelize the sauce.

Let the ribs rest for 10 minutes before slicing and serving with extra BBQ sauce.