Ingredients

   
450g Manila clams (or littleneck)
960g water
5g kombu (dried kelp)
15g sake
1g Diamond Crystal kosher salt
2–3 sprigs mitsuba or scallion, for garnish

Steps

  1. Purge clams in 3% salt water for 1 hour. Rinse well.

  2. Place water, kombu, and clams in a saucepan. Heat over medium. If you have time, steep the kombu in the water first.

  3. When small bubbles appear at the edges, remove kombu. Skim scum from the surface for a clear broth.

  4. When all clams open, add sake. Taste and season with salt if needed.

  5. Serve immediately in individual bowls, garnished with mitsuba or scallion.

Notes

  • This is a clear soup (sumashi-jiru), not miso soup. The broth should be transparent and delicate.
  • Use kombu dashi only — awase dashi (with bonito) is too strong and would overpower the clams.
  • Sake sharpens the broth and masks any residual seafood smell. Taste before and after adding it.
  • Clams get chewy fast — serve as soon as they open. Don’t overcook.
  • Discard any clams that don’t open.
  • De-grit even “ready-to-use” clams. You’ll be surprised what comes out.
  • Keeps refrigerated 2–3 days.