Mix Wet Ingredients: In a medium bowl, whisk together melted butter, brown sugar, and granulated sugar until smooth. Add egg yolk and vanilla extract, whisking until well combined.
Combine Dry Ingredients: Fold in flour, baking soda, and salt using a spatula until a soft dough forms. Gently stir in the chocolate chips.
Prep Air Fryer: Line your air fryer basket with a fitted piece of parchment paper. Drop 3–4 scoops of cookie dough onto the parchment paper, leaving space between them.
Air Fry: Bake at 325°F (160°C) for 7–8 minutes until the edges are golden brown and the centers are still soft.
Cool & Serve: Carefully remove the parchment paper with cookies and let them cool for 3–5 minutes to firm up. Serve warm with a glass of milk!
