To make the teriyaki sauce, boil the balsamic until reduced to 2 tbsp. Put the sake, mirin, soy sauce, sugar and chicken stock in another pan, bring to the boil and reduce by half. Stir in the reduced balsamic vinegar and cool.
STEP 2
Heat the grill to high. put the salmon on an oiled or nonstick baking tray. Brush with a little oil then season. Brush with the teriyaki then grill for 4-5 minutes, brushing a couple more times during cooking until glazed and just cooked through. Serve with steamed rice and pak choy.