Start by pulsing the rolled oats in a blender until they resemble a coarse flour, ensuring a good base for the muffins.
In a large bowl, whisk together the blended cottage cheese, eggs, mashed bananas, and maple syrup until the mixture is smooth and well combined.
Stir in the oat flour, baking powder, cinnamon, and nutmeg into the wet mixture, ensuring everything is mixed evenly.
Gently fold in the finely grated carrots and your choice of raisins or walnuts, being careful not to overmix.
Set your oven to 350°F (175°C), allowing it to reach temperature while you prepare the muffin tin.
Divide the batter evenly into a greased or lined 12-cup muffin tin, filling each cup about 2/3 full.
Place the muffin tin in the preheated oven and bake for 20-25 minutes, checking for doneness with a toothpick inserted into the center; it should come out clean.
Once baked, allow the muffins to cool in the tin for a few minutes before transferring them to a wire rack to cool completely.