How to cook
Put an Oreo cookie at the bottom of each muffin form, then a round, not-too-thick slice of banana on top.
Distribute the prepared mixture into the forms, filling them up nearly to the top.
Put the muffins in a suitable tray and bake in a preheated 275°F (135 °C) oven for 20 min.
After you've taken the muffins out of the oven, leave them to tighten up a bit, then remove them from the forms.
Once they reach room temperature, put them in the fridge to cool for 3-4 hours.