Grilled Miso-Soy Marinated Flank Steak

½ cup light miso (shiro-miso)
¼ cup mirin (sweet Japanese rice wine)
¼ cup sake
2 tablespoons rice wine vinegar
¼ cup soy sauce
¼ cup water
1 tablespoon fresh ginger, finely chopped
2 large garlic cloves, minced
¼ cup canola oil
2 tablespoons sugar
2 pounds flank steak
Salt
Freshly ground black pepper

1. In a large flat plastic container, combine the miso, mirin, sake, vinegar, soy sauce, water, ginger, garlic, oil, and sugar. Stir well. Add the flank steak and turn to coat it all over. Cover and refrigerate overnight.
2. Set a gas grill to medium or light a charcoal grill. Wipe the grill rack with oil. Remove the steak from the container. Tip the marinade into a saucepan. Season the steak with salt and pepper. Cook the meat for 3 minutes on a side or until it registers 125 on a meat thermometer (for medium rare). Transfer to a board and let it sit for 5 minutes.
3. Carve the steak across the grain at an angle into the thinnest possible slices.
4. Bring the marinade to a boil. Let it simmer over medium-high heat for 5 minutes or until thickened. Strain and serve with meat. Serves 8. –Jill Santopietro for The Boston Globe.