In a large skillet or wok, heat vegetable oil to 350°F (about 1 inch deep).
vegetable oil
In a medium bowl, whisk egg whites until frothy. Add chicken pieces and toss to coat.
2 egg whites, 1 ½ pounds boneless skinless chicken breasts
In a separate bowl, mix cornstarch, flour, salt, and pepper.
¼ cup cornstarch, ¼ cup all-purpose flour, ½ teaspoon fine sea salt, ¼ teaspoon freshly ground black pepper
Dredge the egg-coated chicken in the cornstarch mixture, shaking off excess.
Fry chicken in batches until golden brown and crispy, about 3 to 4 minutes per batch. Transfer to a paper towel-lined plate.
For the sauce, combine chicken broth, lemon juice, sugar, honey, lemon zest, and soy sauce in a saucepan over medium heat. In a separate bowl, stir together cornstarch and water to make a slurry and set aside.
¾ cup chicken broth, ⅓ cup fresh lemon juice, ¼ cup granulated sugar, 2 tablespoons honey, 1 tablespoon lemon zest, 1 tablespoon soy sauce, 2 tablespoons cornstarch, 2 tablespoons water
Bring sauce to a simmer, then stir in the slurry. Cook until sauce thickens, about 2-3 minutes.
Remove from heat and stir in sesame oil.
1 teaspoon sesame oil
Toss fried chicken pieces in the warm lemon sauce until well coated.
Garnish with lemon slices, green onions, and sesame seeds before serving, if desired.
lemon slices, thinly sliced green onions, sesame seeds