1. Adjust oven rack to upper-middle position and heat oven to 475 degrees. Line rimmed baking sheet with aluminum foil, top with wire rack, and spray rack with oil spray. Spread flour into shallow dish. Whisk egg whites until foamy in second shallow dish. Spread Corn Flakes crumbs into third shallow dish. Pat chicken dry with paper towels. Working in batches, dredge chicken in flour, dip in egg whites, then coat with Corn Flakes, pressing gently to adhere; lay on prepared wire rack.
2. Spray chicken with oil spray. Bake until chicken registers 160 degrees and coating is brown and crisp, 12 to 15 minutes.
3. Meanwhile, whisk water, soy sauce, apricot jam, hoisin, cornstarch, and vinegar together in bowl. Heat oil in 12-inch skillet over medium heat until shimmering. Add garlic, ginger, and pepper flakes and cook until fragrant, about 1 minute. Whisk in soy sauce mixture, bring to simmer, and cook until thickened, about 2 minutes. Remove from heat, cover, and keep warm.
4. When chicken is cooked, return sauce to simmer over medium-low heat. Add cooked chicken and toss to coat. Serve.