Preheating: Preheat fan oven to 180 degrees C, or 350 degrees F.
Blitz oats: If you’re not using oat flour, blitz the oats in a high speed food processor until finely ground and the consistency of flour is reached
Add Egg, Sweetener, baking powder, oil, bananas: to the food processor and blitz until just combined (30 seconds or so), pausing to scrape down the edges if necessary
Add blueberries: Remove the blade from the food processor and add ½ the blueberries to the batter and gently stir through. (reserve remaining blueberries for the top)
Batter into Muffin Cases: Using either a silicone muffin mold, or paper inserts into a metal muffin tin, spoon the muffin mixture evenly across 10 regular sized muffin cases, filling each one to the top
Add Blueberries: Place the remaining blueberries evenly across the top of the muffins.
Bake: Bake for 22 minutes in a fan oven at 180 degrees C, or 350 degrees F. To test if they are cooked, insert a cake skewer or toothpick into the centre. If it comes out clean, they are cooked. Let muffins cool for 5 to 10 minutes in the muffin tray, then gently remove them and set on a wire rack to cool to room temperature. Once at room temperature, store in an air tight container. On the bench They’ll last for around 3 to 4 days. Alternatively you can freeze them for upto 2 months.