Pre heat oven to 180c / 350F / Gas 4
Mash the bananas and then stir in the oats.
Add the milk & vanilla and stir until fully combined.
Add the berries and stir until evenly distributed through the mixture. I like to break up some of the bigger berries through the mixture.
Grease muffin tray using oil or butter (or use a silicon tray) and pour mixture to the top of each section.
Bake until cooked through (a cocktail stick should come out clean) approx. 18 mins if using a mini muffin tray or approx. 25 min if using a standard tray.