Rinse rice until water runs clear, transfer to a small bowl, add the scallion oil and toss to mix well. Let this stand at room temp for at least 8 hours or overnight.
Soak the scallops in warm water to cover for 20 minutes, drain and flake into small pieces. Combine the rice, scallops, stock and water, bring to a boil, then reduce to med-low heat, stirring often. Simmer until rice is broken down into porridge. Season with salt, to taste.
Combine all sauce ingredients.
Marinate beef in sauce, quickly grill over very hot flames. Serve over warm congee, drizzle with sauce and garnish with fresh ginger and scallion.
Recipe courtesy of Masaharu Morimoto