Beat the chicken breasts lightly between two pieces of plastic wrap.
Combine all the batter ingredients together in a medium sized bowl and mix well. Add the chicken and coat thoroughly.
Heat the wok until hot and add the groundnut oil. Fry the chicken pieces over a moderate heat for about 2 minutes on each side until browned and crisp. Drain on paper towels.
Drain the wok and wipe clean. Add all the ingredients for the sauce and simmer for 2 minutes. Meanwhile cut the chicken into bite sized pieces and arrange on a serving plate.
Pour the sauce over the chicken and serve at once.