Combine the oatmeal, baking powder, cinnamon, and nutmeg in a bowl. Mash 1/3 of the banana. Then add the milk, eggs, honey and the mashed banana to the dry ingredients and mix everything together. Cut the rest of the banana into slices.
Grease an ovenproof glass dish with coconut oil and place half of the sliced bananas and blueberries on the bottom. Pour the batter over it, then pour the rest of the bananas and blueberries over it. Bake everything in the oven for 15-20 minutes (or until golden brown).
Then serve it with some peanut butter or yogurt, if you like - or enjoy it straight out of the oven.