3largecarrots, peeled and finely grated, about 1 cup
1largeFuji or Honeycrisp apple, peeled and finely grated, about 1 cup
For the frosting:
8 ouncesreduced-fat or Greek yogurt cream cheese, at room temperature
Preheat oven to 350°F. Grease a 9x13 inch pan with cooking spray and line with parchment paper, leaving a 1-inch overhang on the 9-inch ends.
To grate the carrots and apples, break into 3-inch pieces and place in the bowl of a food processor. Process for 2-3 minutes, scraping down the sides as needed, until they are finely ground. Alternatively, use the small holes of a box grater to finely grate.
In a large bowl, whisk together the applesauce, oil, buttermilk, eggs, maple syrup, and vanilla.
In a separate bowl, whisk together the flour, baking powder, baking soda, cinnamon and salt.
Add the dry ingredients to the wet mixture. Whisk until just combined; do not overmix.
Use a rubber spatula to fold in the carrots, apples, and any remaining flour residue. Spread into the prepared pan. Bake for 20-25 minutes until the center of the cake is set and a toothpick comes out clean. Remove from oven and let cool on a wire rack for 15 minutes.
Using the parchment paper overhang, carefully remove the cake from the pan to a wire rack to cool completely.
While the cake cools, make the frosting. Using a hand mixer or a stand mixer, beat the cream cheese at medium speed for 2 minutes until very creamy. Add the honey and mix on medium speed for 1 minute until combined and smooth. Use to frost the cooled cake or refrigerated until ready to use. Soften chilled frosting for 30 minutes before spreading.