1. Preheat oven to 350°F.

2. Butter 12 x 16-inch sheet pan and line with parchment paper. 

3. In a medium bowl, whisk together flour, xanthan gum (if needed), baking powder, baking soda, cinnamon, nutmeg, cloves, allspice, and salt. Set aside.

4. In the bowl of your standing mixer, beat sugar, brown sugar and eggs, and cinnamon spice flavoring on medium-high speed until thoroughly combined, about 45 seconds.

5. Reduce speed to low, and slowly add the applesauce, oil, and melted butter. Mix on high for one minute, or until mixture is well mixed and light in color.

6. Turn off mixer and stir in by hand the carrots and dry ingredients until no loose flour remains.

7. Pour into prepared pan. Bake at 350°F for 35 minutes or until a toothpick comes out clean. 

8. Let cake cool, in pan, on a wire rack.

ASSEMBLY:
1. With 2-inch biscuit cutter, cut rounds from cake and pair rounds.

2. One half of the rounds, pipe frosting and top with second round. 

3. Pipe rosette or simple swirl of frosting on top round. 

4. Garnish with a dusting of cinnamon, caramel sauce, or walnuts.