Preheat oven to 320°F / 160°C and line a cookie sheet with parchment paper
Make sure the butter is completely at room temperature. Add it to a large bowl and beat it a little with a wooden spoon just to soften it up further.
Add the sugar and mix until incorporated.
Add the flour and mix until chunky bread crumbs form. Do not overmix, just until it comes together. Ditch the spoon and use your hands to bring it together into a smooth dough.
Add the chocolate and knead through gently.
Roll the dough out on a floured surface and cut into desired shapes
Bake for 10 - 15 minutes, you are not looking for them to be golden brown, they will still be fairly pale once baked
Remove from the oven and immediately sprinkle with a generous amount of sugar. Once they have cooled, tap off the excess sugar