Preparation Combine soy sauce, green onions, 4 tablespoons oil, vinegar, sake, brown sugar, and garlic in 13x9x2-inch glass baking dish; whisk marinade to blend. Add shrimp and toss to coat. Refrigerate at least 30 minutes and up to 1 hour, turning shrimp occasionally. Blend mayonnaise and ginger in food processor until smooth. Transfer ginger aioli to small bowl and refrigerate. Drain marinade from shrimp into small saucepan; bring to boil. Whisk 2 tablespoons boiled marinade into ginger aioli; reserve remaining boiled marinade. Heat remaining 2 tablespoons oil in heavy large skillet over medium-high heat. Add shrimp; sauté until just opaque in center, about 4 minutes. Mound rice in center of plates. Arrange shrimp around rice; drizzle with ginger aioli. Serve, passing reserved boiled marinade.
Preparation Combine soy sauce, green onions, 4 tablespoons oil, vinegar, sake, brown sugar, and garlic in 13x9x2-inch glass baking dish; whisk marinade to blend. Add shrimp and toss to coat. Refrigerate at least 30 minutes and up to 1 hour, turning shrimp occasionally. Blend mayonnaise and ginger in food processor until smooth. Transfer ginger aioli to small bowl and refrigerate. Drain marinade from shrimp into small saucepan; bring to boil. Whisk 2 tablespoons boiled marinade into ginger aioli; reserve remaining boiled marinade. Heat remaining 2 tablespoons oil in heavy large skillet over medium-high heat. Add shrimp; sauté until just opaque in center, about 4 minutes. Mound rice in center of plates. Arrange shrimp around rice; drizzle with ginger aioli. Serve, passing reserved boiled marinade.