• 20–30 small hard-shelled clams
• Salted water
• 1 quart water
• 5–6-inch piece of konbu (kelp)
• ¼ teaspoon salt
• ½ teaspoon soy sauce
• ¼ teaspoon saké (rice wine)
• 2 tablespoons Shinshū Ichi miso (medium bean paste)
• 1–2 scallion(s), finely minced

Scrub the shells of the clams with a stiff brush. Then soak the clams in a large bowl of lightly salted cold water (¼ teaspoon salt for every cup) for 30–40 minutes, or until the shells have opened slightly (the clams “breathe” this way). With your hand, stir up the clams and water; the shells will close promptly. Pour off the sandy water and repeat this cleaning procedure two or three more times. Rinse the clams very well after the final soak.

In a large pot, place the clams, in their shells, in 1 quart of cold water. Add the piece of kelp and bring the water to a boil, uncovered, over high heat. The clams will open and the kelp expand. Reduce the heat, discard the kelp, and simmer for 3–4 minutes. Strain the broth through a cloth-lined colander.

Carefully rinse off any froth or sand that may be clinging to the clams and their shells. Divide the clams among 4 individual soup bowls.

Season the strained clam broth with the salt, soy sauce and rice wine. Use a small amount of warm broth to dissolve the bean paste in a separate bowl, then combine with the seasoned clam broth in a saucepan and heat. Pour it over the clams in individual soup bowls and garnish with the minced scallions. Serve immediately.