Add the chicken, Cajun seasoning, and oil to a large bowl. Toss until the thighs are evenly coated.
Arrange the chicken thighs in the air fryer basket skin-side down, leaving space between each piece.
Air fry at 400°F for 11–12 minutes.
Flip the chicken skin-side up and cook for another 11–12 minutes, or until the thickest part reaches at least 165°F and the skin is crisp enough for you.
Notes
Chicken size: Thighs vary in size, so use the internal temperature to determine when they’re done.
Don’t crowd the basket: Leave space between the thighs so hot air can circulate and the skin can crisp.
Cajun seasoning: If using a store-bought blend, adjust the amount based on how salty or spicy it is.
Boneless thighs: Boneless, skinless thighs cook faster, so begin checking for doneness sooner.