You’ll love these gluten free chocolate sandwich cookies, with their decadent, rich dark chocolate ganache filling and the crumbly, buttery gluten free cookies. They’re super simple to make and look absolutely amazing – like something straight out of a food magazine!
In a bowl, sift together the gluten free flour, powdered sugar, xanthan gum and salt.
Add the cubed cold unsalted butter, and use your fingers to rub the flour and butter together until the mixture resembles fine breadcrumbs.
Add the egg yolks and mix together with the fork.
Add the cold water, 1 tbsp at a time, stirring well with a fork after each addition. After you've added about 3 - 4 tbsp of water, use your hands to bring the dough together in a ball. Knead it together briefly to get a smooth cookie dough – if there are too many dried bits, sprinkle with a bit of cold water and briefly knead again.
Wrap the finished cookie dough into cling film and refrigerate for 30 minutes to 1 hour.
Pre-heat the oven to 355 ºF (180 ºC) and line a baking sheet with baking/greaseproof paper.
Roll out the cookie dough until it's about 3 - 4 mm thin. Use a round cookie cutter (I used one about 2 inches/5 cm in diameter) to cut out the cookies.
Transfer the cookies onto the lined baking sheet and bake them in the pre-heated oven at 355 ºF (180 ºC) for about 15 minutes or until light golden brown.
Allow to cool. In the mean time, make the dark chocolate ganache.
Place the chopped dark chocolate into a heat-proof bowl.
In a saucepan, heat the heavy/double cream until it just starts boiling.
Pour the hot heavy/double cream over the chopped dark chocolate. Allow to stand for 5 minutes, then stir well with a spatula or spoon, until you get a smooth glossy chocolate ganache.
Allow the chocolate ganache to cool, either at room temperature or in the fridge for a few minutes, until it firms up so that it's not too runny but can be piped.
Transfer the chocolate ganache into a piping bag with a large round nozzle, and pipe it onto half of the baked (and cooled) cookies. Make the sandwich cookies and drizzle them with the melted dark chocolate.
The gluten free chocolate sandwich cookies keep well in an air-tight container in a cool dry place for about one week.