Heat a frying pan over medium heat and cook the dried horse mackerel skin-side down for 5–6 minutes. Flip and cook for another 3 minutes until fully cooked. Let cool, remove bones, and roughly flake the fish.

Slice the cucumber into rounds, trim and slice the myoga, and cut the shiso leaves into thin strips.

In a mortar, grind the flaked fish and white sesame seeds together.

In a bowl, combine the ground fish mixture with miso. Gradually add cold water while mixing to create a smooth soup base.