To make the Vinaigrette, mix the soy sauce, lemon juice, vinegar, sugar, and peppercorns in a microwave-safe bowl. Heat for one minute and set aside.
Bring the water, ginger, and onion to a boil in a medium sized saucepan over medium heat. Lower the heat to a simmer and add the chicken breasts. Cook for 15 minutes.
Turn off the heat and let chicken sit in the hot liquid
for 10 minutes. Remove the chicken from the stock, and when it is cool enough to handle, shred the chicken with your hands. Place the chicken back into the stock in a bowl and refrigerate until you are ready to use.
Lightly scrape the skin of the mini or English cucumbers with a paring knife.
5 If using mini cucumbers cut them into 11⁄2 inch (3.75 cm) chunks. If you are using an English or Kirby cucumber cut them in half lengthwise, and then into 11⁄2 inch (3.75 cm) chunks.
Place a chunk of cucumber under the broad part of
a kitchen knife. With your fist, hit the top of the blade once, and lightly crush the cucumber. Repeat with the remaining pieces.
Arrange a layer of the crushed cucumbers around a large serving platter. Remove the cold chicken from the stock and place it down the center of the platter. Surround the chicken with the tomato wedges and top it with green onions.
In a stainless steel ladle or small pot, heat the sesame
oil over a low flame until bubbles appear, approximately one minute. Turn off the heat and pour the oil evenly over the green onions and chicken. Strain the Vinaigrette and drizzle it over the chicken and vegetables. Add salt and pepper to taste.