Preheat the oven to 350°F (175°C) and grease or line a muffin tin with paper liners.
Blend wet ingredients: In a large bowl, mash the ripe banana, then add the almond butter, egg, honey, and vanilla extract. Whisk until everything is well combined.
Add dry ingredients: Stir in the oats, ground flaxseed, baking soda, cinnamon, and ginger. Mix until fully incorporated.
Fold in fruits and nuts: Gently fold in the grated carrots, grated apple, raisins, and chopped walnuts until evenly distributed.
Spoon into muffin tin: Divide the batter evenly among the prepared muffin cups, filling each about 3/4 full.
Bake: Place the muffin tin in the oven and bake for 18-22 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Let Them Rest: After baking, let the muffins sit in the pan for about five minutes. Then, gently move them to a wire rack to cool completely.
Store: These muffins can be stored in an airtight container at room temperature for up to 3 days or in the fridge for up to a week. They also freeze well, making them a great option for meal prep.