AIR FRYER: Preheat air fryer to 400° F. Prep your fryer basket with cooking spray/oil.
OVEN: Preheat oven to 425° F. Line a baking sheet with foil and place a wire cooking rack on top.*
Remove chicken from packaging and pat dry each side with a paper towel.**
Season each side of the chicken with salt and pepper and transfer to appropriate cooking vessel for cooking method, skin side up. Drizzle skin with olive oil.
AIR FRYER: Cook Chicken for 12-15 minutes, or until skin is crisp and golden. Flip and cook for an additional 6 minutes.
OVEN: Bake chicken thighs for 35-40 minutes, or until skin crispy and golden brown. No need to flip.
While the chicken cooks, combine apple cider, honey, dijon, and apple cider vinegar in a small saucepan. Bring mixture to a boil, then reduce heat to low and simmer until reduced and bubbles look thick. About 15-18 minutes-- I do this as the chicken cooks in the airfryer. For oven users, start your glaze about 1/2 way through cooking the chicken.
Just before serving, turn off heat and add butter and rosemary sprig. Stir to combine and serve over top the chicken.