Coat chicken in 1/4 cup cornstarch, set aside.

Beat eggs, salt& pepper in a bowl until smooth. Stir in flour & baking powder until no large lumps remain. Mix in chicken until evenly coated.

Heat vegetable oil in wok or skillet over high heat. Drop in chicken pieces; crook until golden brown and not pink inside about 12 min. Set chicken aside & keep warm.

Reduce heat to medium- high & stir in sesame oil, ginger & green onion. Cook & stir until onion is limp and ginger begins to brown, 1 min. zPour in water, vinegar & sugar; bring to a boil. Dissolve the cornstarch in soy sauce and add to simmering vinegar along with oyster sauce and ketchup. Stir until sauce is thick and no longer cloudy. Stir in chicken & simmer till hot.