1.) In a small food processor or immersion blender, add the green onions, garlic, sugar, pepper, fish sauce, soy sauce, and oil and grind into a fine paste. Set aside.
2.) Trim and discard the silverskin and excess fat from the ribs, then cut the rack into individual ribs and place them in a large resealable storage bag.
3.) Pour the marinade into the bag, then seal and massage the marinade into the ribs. Place the ribs in the refrigerator and marinate for at least 4 hours, or up to 2 days.
4.) If grilling, preheat the grill over medium. Grill the ribs for 15 minutes, then flip and grill for another 15 minutes. The ribs are done when the flesh starts to shrink away from the bone.
5.) If baking, preheat the oven to 375° F. Place the ribs onto a wire rack-lined baking pan. Place the pan on the top rack of the oven and roast for 40 minutes, rotating the pan halfway through the cooking time to ensure even cooking. The ribs are done when the flesh shrinks away from the bone.
6.) Remove the ribs from the grill or oven. Serve with rice and a side of tomatoes and cucumbers.