Whisk soy sauce, brown sugar, rice vinegar, sesame oil, garlic, ginger, and pepper. Add green onions and sesame seeds.

Place ribs in a zip-top bag and pour marinade over. Press out air and refrigerate at least 2 hours, up to overnight.

Heat grill to medium-high, about 450°F. Oil the grate lightly.

Remove ribs from marinade and shake off excess. Grill 2–3 minutes per side for medium, longer if thicker.

Let rest 5 minutes before slicing across the bone. Serve with rice or salad.