Preheat your oven to 350°F, line a sheet tray with foil.
Remove the membrane from the back of the ribs and cut the rack in half to fit into a baking tray.
Place the ribs on a large sheet of aluminum foil and set aside.
In a small bowl, mix together the brown sugar, paprika, black pepper, salt, cumin, garlic powder, onion powder, chili powder, and dried mustard. Use a fork to break up any clumps in the brown sugar.