Preheat the oven to 180ºC/350ºF/Gas Mark 6. Line muffin trays with the paper cases. Heat the butter and honey over a medium heat. In a bowl, mix the flour, oatmeal, baking powder, cinnamon, apple, bananas and blueberries, and combine.
In another bowl, whisk the milk, oils and eggs and pour into the flour mixture, along with the butter and honey. Gently combine. Fill each case with the mixture and bake for 30 minutes.