Preparation

1. Preheat the oven to 180ºC/160°C Fan/gas mark 4/350ºF and line a couple of baking sheets with baking parchment. Spread chocolate chips on a tray and freeze so that they don’t melt while baking Roughly chop the dark chocolate, and melt it over a pan of simmering water. Once it starts to melt you can add semi sweet chocolate chips. Set aside to cool a little. In another bowl, mix together the buckwheat flour, cocoa, baking soda, salt, and espresso powder.

2. In a separate bowl, cream together the butter and sugar with the vanilla extract until a dark caramel colour and fluffy, using a spatula to scrape down the sides of the bowl. Beat in the cooled, melted chocolate then add the eggs one by one. Scrape down the sides of the bowl again, reduce the speed to low, and carefully beat in the dry ingredients.

3. Using a wooden spoon or a spatula, fold in the cold chocolate chips. Arrange rounded dollops of the dough onto a lined sheet pan. Chill sheet pans for 15 minutes before baking. Bake until the cookies are just set at the edges, but otherwise seem undercooked, 9–10 minutes. Remove the sheet from the oven and let the cookies sit on the warm tray for another 10 minutes before transferring them to a wire rack to cool. When the tray is cool, or you have another one lined and ready to go, take the bowl of dough out of the fridge and proceed as before.