In a bowl, marinate the chicken in the garlic, soy sauce, five spice, garlic powder, white pepper, and salt for 30 minutes. If you are air frying or baking, add a 1/2 tablespoon oil to the marinade.

Lightly pat the chicken dry with paper towels. Place the cornstarch and potato starch in a bowl and, working in batches, toss and coat several pieces of chicken, making sure they are well coated. Alternatively, put the cornstarch and potato starch in a bag or container, add the chicken, and shake to coat. The chicken should be well coated and look fairly dry.

Prepare a wire cooling rack over a paper towel lined rimmed baking sheet. Heat up 2 - 2.5 inches of oil in a deep heavy bottomed pot until it reaches 325°F. It doesn’t need to be too deep, it depends on the size of your chicken. Use a pair of tongs to gently add a couple of pieces of chicken to the hot oil, being careful not to overcrowd. Fry in batches until lightly golden, about 1 1/2 minutes. Remove from the oil and let rest on your prepared wire rack. Repeat with the remaining chicken until all of it has been fried once.

Turn the heat up to 350°F and fry the chicken a second time around until deeply golden and crispy, another 1-2 minutes. Drain on the wire rack, sprinkle with the extra spice mix if desired, and enjoy immediately!