- 75g/2¾oz unsalted butter
- 275g/9¾oz plain flour
- 1 tsp bicarbonate of soda
- 2 tsp baking powder
- ¼ tsp ground cinnamon
- 120g/4¼oz golden caster sugar
- 100g/3½oz dark or milk chocolate chips (or a mixture)
- ¼ tsp fine salt
- 2 tbsp flavourless oil, such as sunflower or light rapeseed, plus extra for greasing
- 100ml/3½fl oz milk
- 1 large free-range egg
- 1 tsp vanilla extract
- 250g/9oz ripe banana (about 3 large bananas), mashed
- seeds or chopped nuts, for decorating (optional)
Preheat the oven to 220C/200C Fan/Gas 7 and grease a 12-hole muffin tin using a little of the oil (or line the holes with paper cases).
Melt the butter in a microwave or small saucepan then leave to cool for a couple of minutes.
Combine the flour, bicarbonate of soda, baking powder, cinnamon, sugar, chocolate chips and salt in a large bowl.
Place the melted butter, oil, milk, egg and vanilla in a separate large bowl and whisk until well mixed. Stir in the mashed banana and then tip into the bowl of dry ingredients. Fold together gently with a big metal spoon or spatula until all the flour is just wet but before the mixture becomes smooth – do not over mix.
Divide the mixture between the holes in the muffin tin. Top with the seeds or nuts, if using. Bake for 13–15 minutes until golden on top and a skewer poked into the centre of a muffin comes out clean. Leave to cool on a wire rack and eat slightly warm or at room temperature. They can also be stored in an airtight container for up to two days or in the freezer for up to two months.