Fill a 4-quart sauce pot with 6 cups salted water. Add the chicken and bring to a simmer over medium-high heat. Cook until the chicken is no longer pink inside, about 10 minutes. Remove chicken from the water and let cool. Do not discard the water. While the chicken cooks, prepare the vegetables.

• Core and thinly slice the cabbage.
• Cut the cucumber into thin half-moon slices.
• Cut the pepper into strips; discard the seeds.
• Chop the almonds.

Transfer the vegetables and the chopped almonds to a large salad bowl.

Bring the chicken poaching water to a boil over high heat. Add the udon noodles and cook until tender, about 6 minutes. Drain the noodles and rinse with cold water. Transfer the noodles to the bowl with the vegetables.

• Chop the scallions.
• With the side of a knife, mash the garlic to a coarse paste.
• Grate the ginger.

In an 8-inch frying pan over medium heat, warm ¼ cup oil until hot but not smoking. Add the scallions, garlic, ginger, and peppercorns and cook until the scallions have softened, about 5 minutes.
While the scallion oil cooks, shred or slice the chicken into bite-size pieces and add to the salad bowl.

Add the dressing to the salad and toss to coat. Transfer to individual bowls and serve with the scallion oil on the side.