Preheat your oven to 275°F (135°C).
Mix together the brown sugar, salt, paprika, black pepper, onion powder, garlic powder, and cayenne pepper in a bowl.
Rub 3 tablespoons of the spice blend all over the ribs, keeping the remaining blend for later.
Place the ribs on a large piece of heavy-duty aluminum foil and pour the cola over them.
Fold the edges of the foil together and seal them tightly to create a packet.
Place the packet on a baking sheet and bake for 2.5-3 hours until the meat is tender.
Remove the ribs from the foil and brush with barbecue sauce.
Preheat your grill to medium-high heat and grill the ribs for 5-7 minutes on each side until slightly charred.