1. In a bowl, whisk together flour, sugar, baking powder, baking soda and salt.
2. Add the chocolate chips and mix lightly.
3. In another bowl, whisk the egg, milk, melted butter and vanilla extract.
4. Add the wet mixture to the dry ingredients.
5. Gently mix until just combined. Do not overmix.
6. Line 6 muffin cups with paper liners and fill each about 3/4 full.
7. Preheat the Domestica Air Fryer Oven to 170°C for 2–3 minutes.
8. Place the muffin cups in the air fryer basket or suitable baking tray.
9. Bake at 170°C for 13–15 minutes.
10. Check with a toothpick inserted into the centre. It should come out clean or with a few moist crumbs.
11. Allow the muffins to cool for 5 minutes before serving.