DASHI

Cup of Yum
1. Put the dried kombu in a pot with 6 cups of water. Turn the heat to medium-low and let the water warm slowly. Eventually you will see small bubbles form at the edges of the kombu. When you see this, remove the seaweed.
2. Turn the heat to high and bring the broth to a boil. Drop in the bonito flakes and stir to combine. Turn off the heat, cover the pot and let this steep for 2 to 3 minutes, no more.
3. Strain the broth into a container and reserve. (See notes below if you want to make a secondary dashi with the leftover kombu and fish flakes.)

SOUP

1. In a medium pot, heat the sesame oil over medium-high heat. Cook the minced garlic for a minute, maybe two, but don't let it brown. As soon as it starts to look tan, add the sake and soy sauce. As soon as this comes to a boil, add the reserved dashi. Bring this to a gentle simmer.
2. Add the green thing -- wakame, sea vegetable or spinach -- and the clams. Bring the pot back to a strong simmer, then cover the pot. Let this cook undisturbed 2 minutes, then check for open clams. Pick each one out as they open. Keep cooking for up to 6 minutes (certain species, like Western Littlenecks, need more time to cook than do Manila or topneck clams), picking out each clam as it opens. Any unopened after that time, discard.
3. To finish, return all the clams to the broth, drop the heat to low, and add the chives. Serve at once.