1/2 cup celery pieces
1/2 cup sliced onion
1 teaspoon roasted sesame oil
4 cups water
1 1/2 tablespoons miso
Nori for garnish

Chop the celery into 2 cm pieces and finely slice the onion.
Sauté the celery and onion in the sesame oil for 3-5 minutes. Add the water and bring to a boil. Reduce the heat and simmer, covered, for 15 minutes.
Purée the miso in a quarter cup of the soup broth. Return the purée to the pot, stir, and simmer for a further 3-5 minutes.
Garnish with nori strips.