Step 1 Preheat the oven to 180°C (350°F) or 160°C (315°F) fan-forced. Grease a 9 cm x 19 cm (3½ in x 7½ in, base measurement) loaf (bar) tin with melted butter and line the base and two long sides with one piece of baking paper. Step 2 Put the orange zest and flesh, brown sugar, butter, and egg in the bowl of a food processor and process until well combined and smooth. Add the milk and dates and process until just combined. Add the flours, baking powder, and bicarbonate of soda and pulse until just combined. Step 3 Pour the cake batter into the prepared tin and smooth the surface. Bake in the preheated oven for 50 minutes or until a skewer inserted in the center comes out clean. Step 4 Leave the loaf to stand in the tin for 5 minutes before turning out onto a wire rack to cool completely. Dust with icing sugar and serve in slices.
