Mix the white sugar, brown sugar, ancho chile powder,black pepper, salt, cumin, dry mustard, cayenne pepper, and chipotle pepper in a bowl until mixed.
Place the ribs meat-side down on aluminum foil. Poke the back of rack several times with a knife.
Apply a heavy coating of dry rub to all sides of rib rack.
With rib rack meat-side down, fold foil around it to create a tight seal. Transfer to sheet pan.
Bake in preheated oven until tender and cooked through, about 2 hours. Remove and cool 15 minutes.
Increase oven temperature to 350 degrees Fahrenheit.
Open foil, drain and discard extra juices and fat. Brush barbeque sauce on all sides of the meat.
Place rack meat-side up and return to oven, leaving foil open. Bake for 10 minutes, remove from oven, and brush another layer of barbeque sauce on meat-side only. Repeat baking and brushing with sauce 4 more times, for a total of 50 minutes baking time.
Cut rack into individual rib segments and serve with extra barbeque sauce.