Line a baking sheet with baking paper and put to one side for now.
In a stand mixer or mixing bowl, add the butter and sugar. Mix together until light, fluffy and smooth.
Add the flour and combine to get a smooth paste. It may look a little crumbly, but it will hold together.
Lightly flour a work surface and roll out your dough to approximately 0.5cm (1/4 an inch) thick.
Using a cutter, cut into 10-12 rounds and place on the baking sheet. You'll probably end up with one biscuit made up of the leftovers from the rest - this is my favourite as it's always the first to get eaten!
Put the biscuits in the fridge for 20-30 minutes to firm up. Preheat the oven to 330 ºF or 165 ºC.
Sprinkle some caster sugar on the top, and then pop in the oven for 13-15 minutes or until golden brown on the top.
When they're ready, remove the biscuits from the oven and let them cool on a wire rack. Enjoy with a cup of tea.