1 pound boneless, skinless chicken thighs, sliced into 1-inch cubes
1 1/2 cups cornstarch
1/2 teaspoon salt
1/2 teaspoon freshly ground black pepper
3 peanut or vegetable oil for frying, plus 1 tablespoon for stir-frying
8 dried whole red chilis, or substitute 1/4 teaspoon dried red chili flakes
2 cloves garlic, minced
1 teaspoon white sesame seeds, for garnish
Scallions, green parts thinly sliced, for garnish
Marinade:
1 tablespoons soy sauce
1 tablespoon Chinese rice wine or dry sherry
2 egg whites
Sauce:
1/4 cup chicken stock, or substitute water
1 1/2 tablespoons tomato paste
1 tablespoon soy sauce
1 tablespoon rice vinegar
1 teaspoon hoisin sauce
1 teaspoon chili paste
1 teaspoons sesame oil
1 tablespoon sugar
1 teaspoon cornstarch
Prepare the marinade: In a large bowl, combine the soy sauce, rice wine, and egg whites. Coat the chicken to the marinade mixture and let sit for 10 minutes.
Prepare the sauce: In a small bowl, combine the chicken stock, tomato paste, sugar, soy sauce, rice vinegar, hoisin sauce, chili paste, sesame oil, sugar, and the 1 teaspoon of cornstarch. Stir until the sugar and cornstarch are dissolved. Set the sauce aside.
In a large bowl or deep plate, toss the 1 1/2 cups cornstarch with the salt and pepper. Coat the marinated chicken in the cornstarch and shake off any excess before frying.
Heat the 3 cups of peanut or vegetable oil in your wok until it registers 350°F on an instant-read oil thermometer. Working in 2 or 3 batches, add the first batch of chicken cubes and fry until golden brown on the outside and cooked through, about 4 to 5 minutes. Remove the chicken with a slotted spoon and drain on paper towels. Repeat with the rest of the chicken.
Drain the oil into a heatproof container and save for discarding. Wipe the wok with a paper towel to remove any brown bits, but don’t wash.
Reheat the wok or skillet over medium-high heat. Add another 1 tablespoon of oil and swirl to coat the base and sides. Add the dried chilis and garlic to the wok and stir-fry until just fragrant, about 20 seconds. Pour in the sauce mixture and stir until thickened, about 1 to 2 minutes.
Return the chicken to the wok and stir well to coat with sauce. Transfer the chicken to a serving dish. Garnish with white sesame seeds and scallions. Serve with white rice and vegetables.