Add all ingredients to a large bowl and toss well to coat. If you have the time, cover the bowl and let the chicken marinade in the fridge for 20 minutes (or up to 24 hours).
Skewer the chicken while you preheat the air fryer to 400F. (I like to use 4 skewers so each skewer is 1 serving.)
Cook the chicken until it reaches an internal temperature of 165F, which takes about 12 to 14 minutes, flipping once halfway through. Spoon half of the garlic butter on the chicken when you flip it halfway.
For the Garlic Butter:
While the chicken is cooking, make the garlic butter. To do so, stir together all ingredients in a bowl (if you want to mellow the flavor of the garlic, see the Notes section below).
Divide the garlic butter into 2 bowls to avoid cross-contamination when you brush it on the chicken.
To Serve:
Serve the chicken skewers with the rest of the garlic butter for dipping or drizzling on top. (Note the the garlic butter will thicken as the butter cools, but you can pop it in the microwave for 5-second intervals to melt it again.)
Notes
Storage: Store leftovers covered in the fridge for up to 4 days.
To Mellow the Flavor of the Garlic: You can briefly heat it in the microwave or on the stovetop. To make it in the microwave, add the butter and garlic to a microwave-safe bowl and microwave for 1 minute, stopping to stir the mixture every 15 seconds. Stir in the remaining garlic butter ingredients. To make it on the stovetop, add the butter and garlic to a small saucepan over medium-low heat on the stovetop. Once the butter is melted, cook for 30 seconds, stirring constantly. Remove from the heat and stir in the remaining garlic butter ingredients.
You Can Cut the Garlic Butter in Half: This amount of garlic butter makes enough so you can dip the cooked chicken in it when serving. You can cut the amount of garlic butter in half and you'll have enough to just brush it on the chicken.
How to Make This in the Oven:Preheat the oven to 500F, put the chicken skewers on a baking tray, and roast about 15 minutes, basting with the garlic butter when there's 3 minutes left. If you want to brown the chicken more, turn the broiler on once the chicken is almost fully cooked. This should take less than 5 minutes, and I recommend staying with it because every broiler is different.
How to Grill This: Preheat a grill to medium-high. Grill the chicken until it’s charred and fully cooked in the center, about 6 to 8 minutes per side (flipping the skewers once and basting with the garlic butter after flipping).