Serves: 12
Preparation time: 1 hour 20 minutes
Cook time: 15 mins
1. Use a large kitchen knife to roughly chop the chocolate into chunky morsels, then set aside.
2. With an electric mixer, mix the butter, both sugars and vanilla together for just a few moments, then beat in the egg.
3. Sift the flour into the bowl along with the baking powder, baking soda and salt, then stir with a wooden spoon until only just combined. Overmixing will toughen the dough.
4. Tumble in the fragmented chocolate, and quickly mix through evenly.
5. Wrap the dough in baking paper and leave in the fridge to chill for around 1 hour.
6. Preheat the oven to 180°C/160°C/Gas Mark 4, and line a flat baking tray with baking paper.
7. When chilled, use a spoon or ice-cream scoop to portion out 12 dough balls and space evenly on the baking tray.
8. Bake for 10 minutes, until puffy domes rise in the middle.
9. Remove from the oven and lightly lift and drop the baking tray on the worktop to deflate the puffiness and give them a rugged crackle on top.
10. Return the tray to the oven and cook for a further 5 minutes, until the rims are golden.
11. Allow the cookies to rest on the tray for a few minutes to firm up, then move to a wire rack to cool.
Tip: After chilling the dough, try baking just one cookie to test if the dough is ready. If it spreads out too much, return the dough to the fridge for another 20 minutes or so.
