2 cups green split peas
3-inch piece kombu (optional)
2 teaspoons vegetable oil
1 large onion, thinly sliced into half moons
1 large carrot, diced
1 rib celery, thinly sliced
1 1/2 - 2 teaspoons sea salt
1 bay leaf
2 tablespoons minced fresh basil or 1/2 teaspoon dried basil
1/8 - 1/4 teaspoon ground celery seed (optional)
2 tablespoons brown rice or barley miso, dissolved in 2 tablespoons water (or to taste) minced parsley to garnish
Wash peas and combine them with 8 cups water in a 6-quart pot. If desired for flavor, add the kombu. Bring to a boil and skim any foam that rises to the surface, then lower heat and simmer with the lid ajar until the peas are tender (1 to 1 1/4 hours). Check occasionally and add more water as necessary. (It generally takes about 10 cups of water total, but adding it all in the beginning might result in a thin soup.)
Heat the oil in a large skillet and sauté the onion over medium heat for 2 to 3 minutes, or until it is translucent. Add the carrot and celery and a small pinch of the salt and sauté for a few minutes more. Add a little water if necessary to prevent scorching, then cover, and cook over low heat for 10 minutes. Remove from heat and uncover.
When the peas are tender, add sautéed vegetables, remaining salt, and bay leaf and simmer soup for 20 minutes more. Add a little more water, if necessary, and stir frequently to prevent scorching. (If the bottom burns, carefully pour the soup into another pot without scraping the burned portion.) Add herbs and miso. Simmer 2 minutes more. Garnish with parsley and serve hot.