1. Preheat the oven to 350°F/180°C/ Gas Mark 4. Grease and line a 9-inch round springform pan with parchment paper and set aside.
2. Melt the chocolate in a double boiler or in the microwave and let cool slightly.
3. Place all ingredients in the bowl of a food processor and process to a smooth cake batter. If necessary, adjust the consistency by adding a few tablespoons flour.
4. Tip the batter onto the prepared pan and smooth the top. Bake for 45 to 50 minutes or until a wooden toothpick or a skewer inserted in the middle comes out clean.
5. Let the cake cool in the pan before gently removing and placing it on a serving platter. Cut into slices and serve.