In a large bowl, toss together 1 pound boneless chicken thighs chunks, 1/4 teaspoon garlic powder, 1/4 teaspoon onion powder, and 1/4 teaspoon kosher salt until the chicken is lightly coated.
Whisk together 4 large egg whites and 2 tablespoons cornstarch in a large liquid measuring cup until almost frothy, about 1 minute. Drizzle over the chicken mixture until all the pieces are coated and allow to sit for 5 to 10 minutes. In a medium saucepot, heat 1 1/2 cups vegetable oil until it reaches 350 (F). Working in batches, carefully drop a few pieces of chicken one by one into the oil, giving the chicken a gentle stir or so with a heatproof metal spatula to prevent the pieces from sticking, and fry for 2 to 3 minutes or until light golden. Let the pieces drain on a plate lined with paper towels for 2 to 3 minutes. Then drop them back into the oil for 1 minute to really solidify the coating. Repeat until all the pieces are fried, then set aside to cool as you make the sauce.
Next, make the sauce. In a large liquid measuring cup, combine 2 tablespoons cornstarch, 2 tablespoons water, a pinch of garlic powder, a pinch of ground ginger, a pinch of ground red pepper, and a pinch of white pepper. Whisk for about 1 minute to create another frothy slurry. Set aside. Heat a wok or a frying pan over medium heat and add 1 tablespoon oil. Add 3 to 4 pieces dried orange peel and toast for about 20 seconds, being careful not to burn the peel by tossing the orange peel quickly and rapidly. Add 1/2 cup orange juice, 2 tablespoons rice vinegar, 2 tablespoons granulated sugar, 1/2 tablespoon dark soy sauce, and 1/2 tablespoon light soy sauce. Bring the sauce to a simmer and gradually add the cornstarch slurry (from the 4th step), stirring constantly. When the sauce is thick enough to coat the back of a spoon (you won't likely need to use all the slurry), remove from heat. Add the fried chicken (from the 3rd step) and toss quickly. Serve with scallions and steamed white rice, and serve immediately!