1. Preheat the oven to 190°C/170c fan/Gas 5.
2. Line a loaf tin with grease proof paper.
3. Mash the bananas with a fork and put to one side.
4. Next, in a large mixing bowl, cream together the sugar and butter, until the mix is fully combined and pale in colour.
5. Add the eggs one at a time.
6. Add the flour and mix until fully combined.
7. Fold in the banana and blueberries, pour the mix into the prepared loaf tin.
8. Bake in the preheated oven for approximately 20 minutes, by which time the loaf should be golden, rounded, and peeking out of the tin.
9. Allow to cool slightly in their tin before removing to a wire rack.