1. Heat the oven to 180c (fan) and line a 12-hole muffin tin with paper muffin cases.
2. Tip the bicarbonate of soda and flour into a large bowl. Hold back one tablespoon of the sugar, then mix the rest with the flour and the 50 grams of Quaker Oats.
3. Make a hole in the centre of the mixture.
4. In a separate bowl, mash the bananas until nearly smooth.
5. Stir the oil, buttermilk and egg whites in to the mashed banana until evenly mixed.
6. Pour the liquid mixture into the hole and stir quickly and sparingly with a wooden spoon. The mix will look lumpy and may have the odd speck of flour still visible, but don't over-mix.
7. Tip in the blueberries and give it just one more stir.
8. Divide the mix between the muffin cases - they will be quite full - then sprinkle the tops with the final tablespoon of the Quaker Oats and the rest of the sugar.
8. Bake for 20 minutes until risen and golden brown.
9. Cool for 5 minutes in the tray before lifting out on to a rack to cool completely.