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 until the mixture is smooth and well combined.
03 - In a separate medium bowl, combine rolled oats, baking powder, ground cinnamon, and salt. Mix evenly to distribute the leavening and spices throughout the oats.
04 - Add the dry ingredient mixture to the wet ingredients. Stir until just combined, being careful not to overmix. Gently fold in any desired optional add-ins like nuts, chocolate chips, or berries.
05 - Divide the batter evenly among the prepared muffin cups, filling each about 3/4 full. The batter will rise slightly during baking.
06 - Bake for 22-25 minutes, or until the centers are set when lightly touched and the tops are lightly golden brown. A toothpick inserted into the center should come out clean.
07 - Allow the oatmeal cups to cool in the pan for 5 minutes before transferring to a wire rack to cool completely. Serve warm or at room temperature, topped with a dollop of Greek yogurt and optional sliced bananas, honey, or nuts.