Take out the chicken legs if they are in the freezer or wash them properly if the chicken legs are fresh.
You have to defrost them if you have placed them in the freezer.
Now you have to pat dry chicken legs. You can do this with the use of a paper towel.
Now mix all the dry ingredients including brown sugar, kosher salt, black pepper, mustard powder, onion powder, garlic powder, smoked paprika, and cayenne pepper together in a bowl.
Mix them well.
Now place them in a large ziploc bag. Shake so that the dry ingredients all get mixed together.
Now put the chicken legs in the bag.
Add vegetable oil in the bag and shake chicken legs with dry ingredients and vegetable oil .
Make sure to coat the chicken properly.
Now you have to preheat the air fryer for 5 minutes.
Keep in mind to preheat it at 380 degrees Fahrenheit temperature.
Now you have to place the chicken in the air fryer and set the air fryer to air fry for 18 minutes. You have to set the temperature to 380 degrees Fahrenheit.
After 10 minutes, flip the chicken so that both of its sides are completely cooked.
Keep an eye on the internal temperature of the chicken. When it reaches 165 degrees Fahrenheit, it means your chicken is cooked. You can check the internal temperature of the chicken with the use of an instant-read thermometer.