2 very ripe bananas, mashed
150g/5oz blueberries
250g/9oz plain flour
2 tsp baking powder
50g/2oz caster sugar
1 tsp ground cinnamon, plus 陆 tsp extra for the topping
3 tbsp honey
pinch of salt
3 tbsp vegetable oil
1 large free-range egg
185ml/6fl oz milk