Preheat your oven to 275°F.
Remove the silver skin from the back of the ribs, if needed, by using a sharp knife to loosen a corner of the membrane and then pulling it off with a paper towel.
In a small bowl, mix together the brown sugar, smoked paprika, garlic powder, onion powder, salt, and black pepper to make a dry rub.
Rub the dry rub all over the ribs, making sure to coat both sides evenly.
Wrap each rack of ribs in aluminum foil, sealing the edges tightly to prevent any steam from escaping.
Place the foil-wrapped ribs on a baking sheet and bake in the oven for 2 1/2 to 3 hours, or until the meat is tender and easily pulls away from the bone.
Remove the ribs from the oven and carefully unwrap them from the foil. Discard the foil and any accumulated juices.
Increase the oven temperature to 400°F.
Brush the BBQ sauce generously over the ribs, making sure to coat both sides.
Return the ribs to the oven, uncovered, and bake for an additional 10-15 minutes, or until the sauce is caramelized and sticky.
Remove the ribs from the oven and let them rest for a few minutes before cutting into individual portions.
Serve with additional BBQ sauce on the side, if desired.