Preheat oven to 350F. Spray a 9x5-inch loaf pan with cooking spray or line with parchment paper.

In a large bowl, whisk together egg, brown sugar, coconut oil, granulated sugar, sour cream, vanilla extract, cinnamon, and nutmeg.

Incorporate the flour, baking powder, baking soda, and salt into the wet ingredients until just combined.

Gently fold in grated carrots and grated apples until evenly distributed.

Pour the batter into the prepared loaf pan, smoothing the top with a spatula.

Bake for 45 minutes or until a toothpick inserted in the center comes out clean.

Cool in the pan for 15 minutes, then transfer to a wire rack to cool completely before slicing.