Zaru Udon (Cold Udon with Dipping Sauce)

Instructions

1. Add dashi, mirin, and sugar to a small saucepan. Bring to a simmer over medium heat, stirring until sugar dissolves.
2. Add soy sauce. Bring back to a simmer, then turn off heat. Transfer to a heat-resistant container and cool in an ice bath. (Can be made up to 1 week ahead.)
3. Bring a large pot of water to a boil. Add udon noodles and boil for 1 minute (from frozen). Drain in a sieve.
4. Rinse thoroughly under cold running water, working with your hands, until noodles are no longer slippery. Chill briefly in an ice bath (30–60 seconds — no longer or they'll get too firm). Drain well.
5. Divide noodles onto plates with a few ice cubes. Serve tsuyu in individual cups with sliced scallion, grated ginger, and wasabi on the side. Dip noodles to eat.