Preheat oven to 160C. Line 2 baking trays with aluminum foil and
set them aside. Whisk flour, cocoa, baking soda and salt together. In a
separate bowl, combine the butter and 55g of the chocolate. Place the
bowl in the microwave and zap in 15 second bursts, stirring after each
time, till chocolate and butter have melted. Set chocolate mixture
aside to cool slightly.
Using a electric mixer, mix the chocolate mixture, the egg, vanilla
and sugar well. Fold flour mixture in before adding the rest of the
dark chocolate.
Drop tablespoonsful of the dough onto the baking trays, 2 inches
apart. Bake for about 15 minutes or till cookies are flat and crackled,
rotating trays halfway through. Cookies should still be soft when you
take them out. Let cool on wire racks. Store between layers of baking
paper in airtight containers at room temperature for up to 3 days. Makes about 15 cookies