Here is David Bagrizan's dashi and miso soup method
David Bagrizan is the executive chef at The Fifth Floor and he taught an infusion class one year in the restaurant. Best miso soup I've ever had.
Dashi:
5" x 5" piece of kombu
1/2 cup shaved bonito flakes
4 cups cold water
Let the Kombu soak for 30 minutes in the water, simmer for 10 minutes, remove Kombu. Reduce on high heat for 5 minutes, add tuna, remove from the stove and steep 10 minutes, strain in a fine mesh strainer.
Keeps 4 days
Miso Soup
3 cups dashi
3 T red or yellow miso paste
Garnishes: small cubes of tofu, carrots, potato, green onions, wakame, daikon
If you're using carrot, potato or daikon, simmer them until tender in the dashi. Put a fine mesh strainer into the dashi (submerged) and add the miso, use a whisk to work the miso into the soup, lift out strainer. There will be particles of miso in the strainer that you don't want in the finished soup.
Add garnishes to individual bowls, ladle in the miso soup and serve.
Most of my Japanese friends just keep a jar of Han-Dashi in the fridge, the instant dashi powder, they say it's easier.
http://heatherinsf.wordpress.com/2012/04/02/infusion-class-at-the-fifth-floor/
