Remove the chicken from the refrigerator and let sit at room temperature while making the broth.

Reserving a few sprigs for garnish if desired, cut the cilantro bunch in half crosswise, separating the stems and leaves. Use kitchen twine to tie the stems and scallions into a bundle. Chop enough of the cilantro leaves to measure ½ cup and set aside (save the remaining cilantro leaves for another use).

In a large pot (at least 8 quarts), combine the cilantro-scallion bundle with the remaining broth ingredients and bring to a boil over high heat.

Using tongs, lower the chicken into the broth breast side up, letting the liquid flow into the cavity. If the chicken isn’t fully submerged in the broth after flooding the cavity, weigh it down with a plate.

Allow the broth to return to a boil, then reduce the heat to medium and cook for 25 minutes, adjusting the heat as necessary to keep the broth at a bare simmer.

Flip the chicken breast side down after 15 minutes. Turn off the heat, remove the pot from the burner and let the chicken sit in the hot broth for 30 minutes.

Transfer the chicken to a carving board and let rest for 15 minutes.

While the chicken rests, prepare the dressing. In a small bowl, stir together ¼ cup of the poaching broth, the scallions, soy sauce, vegetable oil, ginger, vinegar, sesame oil and sugar.

Using a sharp knife, remove the legs from the chicken by cutting through the thigh joints, then separate the thighs from the drumsticks. Carve the breast meat from the bone and slice each breast crosswise into 4 pieces. Discard the chicken skin, if desired.

Spread the cabbage on a serving platter, then arrange the chicken pieces on top. Pour the dressing over the chicken and sprinkle with the reserved ½ cup of chopped cilantro. Garnish with cilantro sprigs, if desired. Serve warm, cold or at room temperature.