01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners or lightly grease with oil or butter.
02 - In a large bowl, mash the bananas thoroughly. Whisk in eggs, honey or maple syrup, milk, vanilla extract, and melted coconut oil or unsalted butter until the mixture is smooth and well combined.
03 - In a separate bowl, whisk together old-fashioned rolled oats, baking powder, ground cinnamon, and salt until evenly distributed.
04 - Add the dry ingredients to the wet mixture and stir gently until just combined. Fold in any desired optional add-ins such as chopped nuts, chocolate chips, or blueberries.
05 - Divide the batter evenly among the prepared muffin cups, filling each cup approximately three-quarters full.
06 - Bake for 22 to 25 minutes, or until the centers are set and the tops are lightly golden brown.
07 - Allow the oatmeal cups to cool in the pan for 5 minutes, then carefully transfer to a wire rack. Serve warm or at room temperature with a dollop of Greek yogurt and optional toppings of your choice.