In a large bowl, marinate the chicken in the combined soy sauce, vinegar, oil, starch and egg whites for about 20-30 minutes at room temperature.
Mix the sauce ingredients in a bowl, whisk and set aside.
Saute the garlic and ginger in 1 tsp of oil in a saucepan for about a minute until fragrant, add the above sauce, and bring it to a boil. Reduce the heat to low and simmer for about 15 minutes. Add the starch/water mixture and stir until the sauce thickens. Remove from the heat, and cover to keep warm.
In a 2-quart saucepan, bring one quart of water and 1 tbsp oil to a boil over high heat. Reduce the heat to low and add the chicken to the simmering water, stirring to prevent the pieces of chicken from clumping together. Cook until the chicken is opaque, but not cooked through, about 1 minute. Drain the chicken in a colander
In a wok or large sauce pan over high heat, swirl the remaining tablespoon of oil into the wok. Add the chicken and saute for three minutes or until cooked through. Re-stir the sauce mixture and pour half over the chicken. Stir fry, until the chicken is cooked through and the sauce is slightly thickened, about 1-2 minutes. Toss with remaining sauce.
Serve immediately with steamed rice/quinoa and sauteed veggies if desired!