A popular old-timer with a savory vegetarian twist.
Wash the peas several times, until the water is clear (makes soup less gas-forming). Boil and skim off any foam. Then add seaweed, onion, and enough water to cover by one inch. Cover and simmer 30 minutes. Add other veggies, and just enough water to make desired creaminess. Simmer 30 minutes more. Dissolve miso into soup just before serving.