Miso Soup with Black Cod and Green Onions
1 piece kombu, about 3 inches (7.5 cm)
1⁄2 cup (1⁄2 oz./15 g) bonito flakes
2 Tbs. white miso paste
5 oz. (155 g) black cod, cut into 2 to 4 pieces
1 Tbs. olive oil
Salt and freshly ground pepper, to taste
1 green onion, white and tender green parts, thinly sliced
Put 3 cups (24 fl. oz./750 ml) cold water and the kombu in a saucepan over medium heat. Bring to a boil and then remove and discard the kombu. Turn off the heat, add the bonito flakes, stir gently once and let sit for 5 minutes. Strain the soup through a fine-mesh sieve and return the broth to the saucepan.
Put the miso paste in a small bowl and add 1⁄4 cup (2 fl. oz./60 ml) of the warm broth. Stir until the mixture is very smooth. Add the miso mixture to the saucepan and warm gently, taking care not to let the soup come to a boil.
Place a small frying pan over high heat until it is very hot. Season the cod with the oil, salt and pepper and sear until just cooked through, 4 minutes per side.
To serve, ladle the soup into bowls, top with one or two pieces of fish, and sprinkle with green onions.
