1 tbsp. cornstarch
1 tbsp. water
5 tbsp. sake
2 tsp. sugar
5 tbsp. soy sauce

Make a paste of cornstarch and water; add in sake, sugar and soy sauce. Heat sauce in a shallow pan stirring until thickened. Brush on the fish as it comes piping hot off the grill. Also goes well with fried or battered fish.