In a bowl, use a hand mixer to whisk together the softened butter (2oz/ 57g), sugar and egg.
Sift in the all purpose flour, baking powder and salt.
Add the dry ingredients to the wet ingredients and mix until just combined.
Place 4 silicone cupcake moulds into the air fryer basket.
Fill each silicone cupcake mould about two-thirds full with batter.
Bake for 10 minutes on 350 degrees Fahrenheit, or until a toothpick inserted into the center comes out clean.
Remove the cupcakes from the air fryer basket.
Whilst the cupcakes are cooling, make the frosting.
Get a small bowl, whisk together powdered sugar, milk and butter (2oz/60g) until desired consistency is achieved.
Add a drop or two of vanilla extract, if desired.
Place into a piping bag and frost the cupcakes then top with sprinkles.