Makes about 30-35 cookies
- 150 g white chocolate
- 225 g dark chocolate (between 55-65 % is best)
- 125 g unsalted butter, at room temperature
- 200 g soft light brown sugar
- 2 medium eggs, lightly beaten
- 1 teaspoon vanilla extract
- 185 g plain flour
- 40 g cocoa
- 1 teaspoon bicarbonate of soda
- a pinch of salt
- 100g white, milk or dark chocolate
You will also need 2 baking sheets lined with baking parchment
Cut the white chocolate into chunks and set aside.
Chop the dark chocolate and melt in a heat-proof bowl either set over a pan of barely simmering water or in the microwave in short bursts on a low setting. Stir until smooth and leave to cool slightly.
Cream the butter with the soft light brown sugar in a free-standing mixer until pale and light. Scrape down the sides of the bowl with a rubber spatula and gradually add the lightly beaten eggs, mixing well between each addition. Add the vanilla extract and mix again to combine.
Add the melted chocolate and mix until combined. Sift the flour, cocoa, bicarbonate of soda and a pinch of salt into the bowl and mix again until nearly smooth. Add the chopped white chocolate and fold in until the chunks are well distributed throughout the cookie dough.
Lay a sheet of baking parchment on the work surface and spoon half of the dough onto the paper and into a neat sausage shape. Roll the dough into a neat, tight 4-5 cm diameter log and wrap tightly in the paper. Repeat with another sheet of parchment and the remaining dough. Chill the logs in the fridge for a couple of hours or in the freezer for 45 minutes until firm.
Preheat the oven to 170ºC (325ºF) Gas 3 and line two baking sheets with baking parchment.
Unwrap the dough logs and slice into neat rounds each about 1 cm thick and arrange on the baking sheets, leaving a little space between each cookie to allow for them to spread during cooking. Bake on the middle shelf of the preheated oven for 10-11 minutes until just firm. Leave the cookies to cool on the baking sheet for 5 minutes and then transfer to a wire rack and leave until cold.
Melt the remaining white, milk or dark chocolate following the above instructions and using a teaspoon drizzle over the cookies in swirls, Leave until set before serving.