Preheat the air fryer or oven to 325°F. Line a baking sheet with parchment paper.

In a medium mixing bowl, add the butter, dark brown sugar, and maple syrup. Mix together with a spatula to combine completely.

Add in the milk, flour, baking soda, and salt and fold together until a cookie dough forms. Then fold in the chocolate chips. (The chocolate chips are optional and you can leave out if you want a plain sugar cookie!)

Using your hands, form the dough into 6 large balls and place on a parchment paper lined baking sheet. If you’re using your air fryer, then do 3 cookies at a time. If you’re using the oven, then 6 will fit on one baking sheet.

Bake for 13 to 15 minutes or until the middle looks set and the edges are golden brown.

Sprinkle with flaky sea salt immediately after coming out of the oven (optional).