Cut X in flat side of each chestnut. In small saucepan of boiling water, cook chestnuts,
4 at a time, for about 2 minutes or until skins can easily be peeled off. Place peeled nuts in saucepan and cover with water; bring to boil and cook until tender, 5 minutes. Drain and reserve.
In bowl, soak shiitake mushrooms in 1 1/2 cups (375 mL) warm water until tender, about 30 minutes. Drain, reserving liquid; remove stems.
Meanwhile, using kitchen shears, remove backbone from chicken. Cut off wing tips. Cut in half along breastbone. Cut each half between thigh and breast. Cut each breast in half crosswise. Cut each leg between drumstick and thigh.
Cut white and light green parts of onions into 1-inch (2.5 cm) lengths; finely chop dark green parts and set aside. Thinly slice ginger and stack slices; cut into diamond shapes and set aside.
In large shallow Dutch oven or deep skillet, heat oil over medium-high heat; brown chicken, in batches; remove to plate. Drain off all but 1 tablespoon (15 mL) fat. Add onion lengths and ginger; stir-fry for 30 seconds. Add mushrooms and carrots; stir-fry for 1 minute. Stir in reserved mushroom liquid, soy sauce, sugar and wine; bring to boil. Return chicken and any accumulated juices to pan; reduce heat, cover and simmer for
Add chestnuts, Szechuan pepper and white pepper; cook, uncovered, over medium heat until juices run clear when chicken is pierced, about 10 minutes.
Meanwhile, in large pot of boiling salted water, blanch bok choy until tender, about
2 minutes. Drain and toss with sesame oil; arrange around platter and keep warm.
With slotted spoon, arrange chicken on platter; surround with carrots, mushrooms and chestnuts. Add reserved finely chopped green onions to sauce; pour over chicken.