Fry sausage in a skillet until browned on both sides.
Add to a pot, all of the ingredients up until the bay leaf.
Simmer for 25 minutes.
Add the peas and pasta and cook until the pasta is al dente (10 minutes).
Take one cup of the soup broth and blend or whisk it with the miso.
Then add it back to the pot.
Do not continue to cook the soup after the miso has been added as boiling temperatures kill the healthy bacteria in the miso.
Add salt (if needed) and pepper to taste.