In large, dry skillet over medium-high heat, toast walnuts, stirring occasionally, until lightly brown, about 1 to 2 minutes. Set aside for garnish.
Carefully peel back the layers of the lettuce and trim each leaf to form a bowl. Wash the leaves and dry. Set aside.
Heat a large pan or wok over high heat. Add oil and ground chicken. Stir constantly for 2 minutes to break up the chicken. Add the carrot, celery and garlic. Continue cooking for 2 to 3 minutes.
Add the hoisin and soy sauce, cooking wine, white pepper and sesame oil. Stir frequently until chicken is completely cooked, about 2 to 3 minutes.
Serve in lettuce bowls and top with a teaspoon of crushed walnuts and a sprinkling of bean sprouts or fried egg noodles as desired.
Per serving (2 lettuce bowls): about 317 calories, 13 g protein, 24 g fat (2 g saturated fat), 13 g carbohydrates, 2 g fibre, 43 mg cholesterol, 520 mg sodium. %RDI: 4% calcium, 10% iron, 8% vitamin A, 7% vitamin C.