In a mixing bowl, combine flour, baking powder, and salt.

Add diced butter to flour mixture, and with your hands, massage the butter into the flour.

Using a dough hook, knead the dough on medium speed, slowly adding the buttermilk until a dough ball forms.

Lightly dust a flat surface with flour, and flatten dough to 1 1/2 inches thick.

Using a wide mouth mason jar, or something of a similar size, punch out the biscuits. Re-knead and flatten excess dough for more biscuits.

Place biscuits in the air fryer basket, brush tops with melted butter, and cook at 370 for five minutes on each side.