1 lb (500 g) boneless skinless chicken breasts
1 egg white
2 tbsp (30 mL) cornstarch
2 tbsp (30 mL) soy sauce
2 tsp (10 mL) sesame oil Salt to taste
¼ cup (60 mL) vegetabl oil 

SAUCE 

½ cup (125 mL) chicken stock
2 tbsp (30 mL) sherry
2 tbsp (30 mL) soy sauce
1 tbsp (15 mL) Chinese black vinegar or balsamic vinegar
2 tsp (10 mL) sugar
2 tsp (10 mL) sesame oil
4 to 8 small dried red chilies
½ cup (125 mL) roasted unsalted cashews
1 tbsp (15 mL) chopped garlic
1 tbsp (15 mL) chopped ginger
1 tbsp (15 mL) chopped green onion 

TO FINISH 

2 tbsp (30 mL) water
2 tsp (10 mL) cornstarch
2 tbsp (30 mL) slivered green onion

1. Dice chicken into 1-inch (2.5 cm) cubes and place in a bowl. Combine egg white, cornstarch, soy sauce and sesame oil in a bowl and season lightly with salt. Add chicken and stir to coat. 
2. Heat a wok over high heat. Add vegetable oil and swirl carefully to coat. When oil is very hot, remove chicken from marinade, add to wok in batches and fry in oil for 3 minutes or until lightly browned and almost cooked through. Remove from oil and place in a strainer over a bowl to drain. 
3. For the sauce, combine chicken stock, sherry, soy sauce, black vinegar, sugar and sesame oil. 
4. Reheat oil (adding more if needed) in wok. Add red chilies, cashews, garlic, ginger and green onion, and fry for 30 seconds or until fragrant. Immediately stir in sauce and bring to boil. Return chicken to wok and simmer in sauce for 1 minute or until cooked through. To finish, stir water and cornstarch until blended. Add cornstarch mixture slowly, using only enough to thicken. Stir and gently boil. Scatter with green onions and serve.