Rub ribs with sake and sugar mixture. Let stand for 15 minutes.
STEP 2
Combine soy sauce, scallions, garlic, brown sugar, and sesame oil in a bowl. Stir in water until sugar dissolves. Add vegetable oil and pepper. Pour over ribs and coat evenly. Cover and refrigerate for 8 hours or overnight.
STEP 3
Prepare grill: Light coals and let them ash over. Grill ribs directly over coals for 1-2 minutes per side, then move to cooler side and grill until tender, around 5 minutes per side. Alternatively, broil in the oven until done.