Stir-Fried Chicken and Asian Greens

12  ounces  boned, skinned chicken breast halves
2  tablespoons  dry sherry
3/4  cup  fat-skimmed chicken broth
1  tablespoon  soy sauce
1  tablespoon  cornstarch
1/4  teaspoon  white pepper
1  pound  Asian greens
1  tablespoon  vegetable oil
1  tablespoon  minced garlic
1  tablespoon  minced fresh ginger
Salt

Rinse chicken and pat dry. Cut crosswise into strips about 1/8 inch thick and 2
to 3 inches long. In a bowl, mix chicken with sherry. In another small bowl, mix
broth, soy sauce, cornstarch, and white pepper.

Remove and discard any yellow, damaged, or tough leaves from 1 pound
Asian greens. Trim off and discard tough stem ends. For tough stalks, remove
any thick side stems attached to center stalk; discard center stalk and use
stems. Rinse well.

For bok choy: Cut leaves and stalks diagonally or crosswise into 1/4-inch-thick
slices; separate leaves from stalks.

For Chinese mustard or yao choy: Trim stalk ends, especially if fibrous (a
white, woody center is an indication). If skin on stalks is tough, peel off and
discard. Cut greens into 3-inch lengths, separating leaves and thin stems from
thicker stems or stalks. If any pieces are thicker than 1/2 inch, cut to that
thickness
.
Set a 14- to 16-inch wok or 12-inch frying pan over high heat. When hot, stir in
the thick stem pieces and 3 tablespoons water. Cover and cook until pieces
are tender-crisp to bite, 2 to 3 minutes. Add the leaves and thin stems and stir
until leaves are barely wilted, 1 to 2 minutes; pour mixture into a bowl.
Return pan to high heat. When it's hot and any liquid has evaporated, add oil,
garlic, and ginger; stir until garlic begins to brown, about 30 seconds. Add
chicken and stir until no longer pink in the center (cut to test), 2 to 3 minutes.
Stir broth mixture and add to pan; stir until boiling. Return greens to pan and
stir until hot. Add salt to taste and pour into a serving bowl.