These salmon kabobs can be prepared in advance and cooked as you need them.
1/3 cup soy sauce
2 ½ tablespoons rice vinegar
2 tablespoons mirin (rice wine)
3 tablespoons dark brown sugar
2 cloves garlic, crushed
2 tablespoons finely chopped peeled ginger (about a 3” piece)
1 3/4 pounds salmon cut into 1 1/4-inch chunks
3 scallions, checked and chopped
Soak skewers in a bowl of water for 30 minutes.
Bring soy, vinegar, mirin, sugar, garlic and ginger to a boil in a small saucepan, then reduce heat and briskly simmer until reduced to 1/2 cup, about 3 minutes. Divide sauce in half and place in two metal bowls and cool to room temperature.
Toss salmon cubes with sauce in one bowl. Allow to marinate at least 30 minutes.
Preheat broiler or grill pan. Oil surface with a paper towel dampened with canola oil.
Drain skewers, then thread with salmon and put on broiler rack or grill pan. Discard marinade in the bowl. Broil or grill until just cooked through, 4 to 5 minutes. Remove from pan and brush with some of remaining sauce in the other bowl.
Serve kebabs over rice then drizzle with remaining sauce and sprinkle with scallions.