In a medium pot, combine enough water to cover the chicken, along with sliced ginger and scallions. Bring to a rolling boil over medium-high heat, then lower to a gentle simmer. Add the chicken breast, cover, and poach for 10-12 minutes until the internal temperature reaches 165°F.

While the chicken is cooking, prepare an ice bath by filling a large bowl with cold water and ice cubes. Once the chicken is done, transfer it to the ice bath immediately. Let it sit for about 5 minutes before removing and draining.

While the chicken cools, julienne the cucumber into thin strips and arrange neatly on a serving plate.

Once the chicken has cooled, shred it into bite-sized pieces.

In a medium mixing bowl, combine the sauce ingredients and whisk until smooth. Adjust seasoning as needed.

To assemble, place the shredded chicken on top of the cucumber and drizzle the sauce over it. Sprinkle toasted sesame seeds on top.

Let the assembled dish sit for a few moments to allow the flavors to meld. Serve slightly chilled or at room temperature.