1 Heat the oil in a wok or large skillet. Add the ribs and cook on both sides until browned, about 25 minutes.
2 Add the sugar and stir for 10 minutes.
3 Pour off all but 1 tablespoon of fat from the wok. Add the fish sauce and soy sauce and stir for 5 minutes. Add the onions, garlic, bell peppers and scallions. Stir-fry for 3 minutes longer, or until the onions are lightly browned and the peppers are slightly soft. Remove to a serving platter.
4 Sprinkle with black pepper and garnish with coriander sprigs. Serve with rice.