Preheat oven to 400 degrees F (200 degrees C). Line a muffin tin with muffin cups and spray with nonstick baking spray.
Mash the Banana (1). Peel and grate the Carrot (3) with box grater.
In a large bowl add the All-Purpose Flour (1 1/4 cup), Brown Sugar (1/2 cup), Baking Powder (1/2 teaspoon), Baking Soda (1/2 teaspoon), Kosher Salt (1/2 teaspoon), and Ground Cinnamon (1 teaspoon). Mix with a whisk until lumps disappear.
Add the Old Fashioned Rolled Oats (1 cup) and Raisins (1/2 cup) and mix to combine.
In another bowl, mix the shredded carrots, mashed banana, Egg (1), and Heavy Cream (1 cup). Add to the dry and fold with a spatula until all ingredients are incorporated. Batter will be thick but wet.
Spoon equal amounts of batter into each muffin tin. I like mine big so I fill mine up all the way!
Bake for 23-25 minutes.