Pre-heat the oven to 160C fan-forced and line two baking trays with baking paper.
In the bowl of an electric mixer, beat the butter and caster sugar together until light and creamy.
Scrape the sides then beat in the egg.
Add the flour and Milo and mix slowly until a dough forms.
Using a level tablespoon of dough at a time, roll it into balls and place on the trays leaving at least 4cm between each one.
Flatten the balls slightly and bake for 15 minutes.
Leave to rest on the trays for 5 minutes and then transfer to a wire rack to cool completely.
Notes
Store: Store in an air-tight container or freeze in ziplock bags. Tip: You can also make the dough to the rolling stage and freeze the dough balls. Leave to thaw on the oven tray before pressing and baking.