Chop the apple, grate the carrot, and roughly chop the raisins.
Mash the banana until smooth.
Blend oats into fine oat flour using a food processor or blender.
In a bowl, whisk together mashed banana, egg, and Greek yogurt.
In another bowl, mix oat flour with cinnamon, baking powder, baking soda, and salt.
Stir the dry ingredients into the wet mixture until combined.
Fold in apple, carrot, and raisins.
Line a small loaf pan with parchment paper.
Pour in the batter and smooth out the top.
Bake at 350°F (175°C) for 40–45 minutes, or until a toothpick comes out clean.
Let cool, then slice into 4 equal servings.