Preheat your oven to 375°F (190°C). Grease a 24-cup mini muffin pan.

In a medium bowl, combine 2 mashed ripe bananas, grated apple, grated carrot, milk, melted butter, egg, and vanilla extract. Blend until smooth and creamy.

In a separate bowl, whisk together whole wheat flour, rolled oats, ground cinnamon, baking powder, and baking soda. Fold the dry mixture into the wet mixture until combined.

Fill each muffin cup with about 2 tablespoons of the batter, slightly mounded.

Bake for 16-20 minutes, or until a toothpick comes out clean.

Let the muffins cool for about 5 minutes in the pan before transferring to a wire rack.

Serve warm or cooled, and store leftovers in an airtight container.