Instructions

1. Preheat oven to 180°C/350°F/gas 4 and line a 23cm (9inch) square baking tin with parchment paper.
2. Combine all the ingredients in a large bowl and mix together with a wooden spoon until thoroughly mixed.
3. Pour the batter into the prepared tin. Spread the batter out evenly and smooth the top with the back of the spoon or a spatula.
4. Bake for 30-35 minutes until a toothpick comes out clean. Leave to cool in the tin on a wire rack, once cool, remove from tin and cut into 16 or 20 pieces.
5. Will keep for up to 5 days at room temperature in an airtight container.