In a large saucepan, place the chicken skin side down, then add the scallion whites, ginger, garlic and 1 1/2 teaspoons of salt. Add the water and sherry, if using, fully submerging the chicken. Bring to a boil over medium-high, then cover, turn off the heat and let sit until the chicken registers 160ºF, 15 to 20 minutes. Uncover the pan and let the chicken cool in the liquid for 30 to 45 minutes.

Meanwhile, in a small bowl, whisk together the chili oil, tahini, sugar, sesame oil, soy sauce, vinegar, 1 1/2 teaspoons of salt, Sichuan peppercorns, if using, and cayenne.

Remove the chicken from the cooking liquid. Remove and discard the skin and bones, then transfer the meat to a large bowl. Add 2 tablespoons of the dressing, then use a wooden spoon to smash the meat, working the dressing into it and shredding it. Use your fingers to pull the shreds into bite-size pieces. Add the cucumber and three-quarters each of the peanuts and scallion greens. Drizzle with the remaining dressing and toss until evenly coated.Transfer to a serving bowl and sprinkle with the remaining peanuts and scallions.

Tip: Dont boil the chicken for long; the meat will dry out. Residual heat gently poaches the chicken, guaranteeing it stays moist and tender.

** substitute half black peppercorns plus half whole corriander seed