Preheat your oven to 300°F (150°C).
Rinse the spare ribs under cold water and pat dry with paper towels.
Remove the thin membrane from the back of the ribs.
Mix brown sugar, garlic powder, onion powder, smoked paprika, salt, and pepper.
Rub the spice mixture evenly over the ribs.
Place the ribs on a baking sheet lined with foil, bone side down.
Cover the ribs with another layer of foil.
Bake in the oven for 2 hours until tender.
Remove the foil and brush barbecue sauce on the ribs.
Increase oven temperature to 400°F (200°C) and bake for an additional 15-20 minutes.