Pat chicken thighs completely dry with paper towels. In a small bowl, combine garlic powder, smoked paprika, salt, and black pepper. Drizzle chicken with olive oil and rub the spice mixture evenly over all sides of the thighs.
Preheat Air Fryer: Preheat your air fryer to 400°F (200°C) for 3 minutes.
First Cook: Place chicken thighs skin-side down in the air fryer basket, ensuring they don't overlap. Cook for 12 minutes.
Flip and Continue: Flip the thighs skin-side up and cook for an additional 10 minutes.
Make the Glaze: While chicken cooks, whisk together honey, minced garlic, soy sauce, rice vinegar, olive oil, and red pepper flakes (if using) in a small bowl.
Apply Glaze: Brush the honey garlic glaze generously over the chicken thighs. Cook for 3-5 more minutes, until the glaze is caramelized and the internal temperature reaches 165°F (74°C).
Rest and Serve: Let the chicken rest for 5 minutes before serving. Drizzle with any remaining glaze and serve immediately.