Prep. Preheat the oven to 350 degrees F. Add the muffin liners to the muffin tin.
Combine dry ingredients. In a mixing bowl, combine the flour, baking soda, baking powder, salt, cinnamon, granulated sugar, and brown sugar. Set the bowl aside.
Mix the wet ingredients. In a different mixing bowl, mix the melted butter, vanilla, and eggs.
Combine. Stir the dry ingredients into the wet ingredients to form a thick batter.
Add carrots and banana. Carefully fold in the shredded carrot and mashed bananas, but don’t overmix.
Bake. Pour the muffin mixture into the muffin liners, ⅔ of the way full.
Put the crushed pecans on top of each muffin, and then add the muffin pan into the oven. Bake for 15-20 minutes to cook.
Let the muffins cool in the pan for 2-3 minutes, then move the muffins to a wire rack to cool the rest of the way.