Grease 2 baking sheets and line with nonstick baking paper. In a bowl, beat the egg and sugars together until light and creamy. Stir in the vanilla extract and oil. Sift in the flours and cinnamon, then add the coconut, walnuts and chocolate and mix well with a wooden spoon.
Form rounded tablespoonfuls of the mixture into balls and place on the prepared baking sheets, pressing the mixture together with your fingertips if it is crumbly. Bake in a preheated oven, 180°C (350°F), Gas Mark 4, for 12–15 minutes or until golden. Leave to cool slightly on the sheets, then transfer to a wire rack to cool completely.