Preheat your oven to 180 degrees celsius. (360 Fahrenheit)
Sift the flour, baking powder and sugar into a mixing bowl. (If you don't have a sifter or sieve you can use a whisk or fork to make sure the dry ingredients are well combined and lump free.)
Add the chocolate chips to the dry ingredients and mix so they are evenly distributed.
Melt the butter, add the egg, vanilla and milk to the butter and combine.
Fold the wet ingredients into the dry ingredients to make your mini muffin batter. Be careful to not over mix the batter.
Spoon your muffin batter into a mini muffin tray. I grease the tray if I'm using traditional bakeware, but they are usually ok not greased in a silicone muffin tray.
Bake for 10-12 minutes until lightly golden and the centre of the muffin springs back when pressed gently.