Miyazaki Reimen

Prepare dashi: Place kombu in 1200g water and let it soak for 30 minutes. Heat the water gently until just before boiling, then remove the kombu. Bring the water to a boil, turn off the heat, add katsuobushi, and let it steep for 5 minutes. Strain the dashi through a fine-mesh sieve, discarding the katsuobushi.

Prepare the soup: In a large bowl, combine the strained dashi with koikuchi shoyu, rice vinegar, sugar, salt, and sake. Stir until the sugar and salt are fully dissolved. Transfer the soup to a container and chill thoroughly in the refrigerator for at least 2 hours.

Prepare toppings: Slice the pork char siu into thin pieces. Halve the boiled egg lengthwise. Julienne the cucumber into thin strips. Thinly slice the scallion.