In a medium bowl, beat the softened butter and caster sugar together until pale and creamy. If using a Thermomix: Insert the Butterfly into the Thermomix bowl. Add the softened butter, caster sugar and mix for 20 seconds, Speed 4. Scrape down the sides of the bowl and mix for a further 40 seconds, Speed 4 (or until pale and creamy).
Add the egg and vanilla extract and beat until combined. If using a Thermomix: Reduce to Speed 2 and with the butterfly still turning, add the egg and vanilla extract through the MC hole. Increase to Speed 4 for 20 seconds. Remove the butterfly.
Sift over the plain flour, baking powder and salt and beat on low to combine. If using a Thermomix: Add the plain flour, baking powder and salt to the bowl. Mix for 10 seconds, Speed 4. Scrape down the sides of the bowl and repeat for a further 10 seconds.
Divide the dough into 2 equal portions. Using a floured rolling pin, roll out each portion on lightly floured baking paper sheets to ½ cm thick.
Chill the dough on the baking paper sheets in the fridge for at least 1 hour (up to 2 days).
Preheat oven to 175 degrees celsius (fan-forced). Grease and line two baking trays with baking paper.
Use cookie cutters to cut out shapes and place them onto the prepared baking trays, allowing a gap of approximately 8cm between each cookie. Press together and roll out the remaining dough. Cut out more shapes until all of the dough has been used.
Bake the cookies for approximately 10 minutes or until they appear 'dry' on top. Do NOT overcook.
Serve as is, or decorate with royal icing (see notes) or a simple glaze.
Notes
RECIPE NOTES & TIPS
Use room-temperature butter — it creams more easily and gives better lift.
Don’t skip the chilling step — that’s what keeps your cookies from spreading and gives a crisp, defined shape.
Allow room in-between - when placing cookies on the baking trays, as they can spread ever so slightly when baking.
Rotate your baking trays halfway through cooking if your oven has hot spots.
Keep an eye on the baking time — bake just until the tops look dry; the cookies will continue to firm as they cool.
Storage: Store baked cookies in an airtight container at room temperature for up to 1 week. If decorated with icing, separate layers with baking paper to prevent sticking.
Freezing: You can freeze unbaked dough (rolled and cut) for up to 1 month. Defrost in the fridge and bake as directed. You can also freeze fully baked cookies (layered with baking paper) for up to 3 months; thaw at room temperature before serving. If freezing, it's best to leave cookies un-iced.
If your cookies spread too much, next time chill dough slightly longer or reduce oven temperature by 5 °C and increase bake time by 1-2 minutes.
Decorate with royal icing that sets firm or a simple icing glaze.