Mix the flour, cornstarch, baking powder, cinnamon, nutmeg, salt, and baking soda in a medium bowl and set aside.
In a stand mixer with the paddle attachment, beat the softened butter, sugar, and brown sugar on medium for 1 minute until creamy.
Add the vanilla and egg and beat for one minute on medium-low until combined. Scrape down the bowl and mix again.
Slowly mix the dry ingredients into the wet ingredients, beating on low until just combined. Then, scrape down the sides of the bowl and mix again.
Add the shredded coconut, carrots, and oats and mix on low until just combined.
Cover the bowl with plastic wrap and chill for 30 minutes.
Just before the cookies are finished chilling, preheat the oven to 350 degrees and line two baking sheets with parchment paper.
Using a 2-inch cookie scoop, place uniform dough balls two inches apart on the cookie sheets.
Bake the cookies for 9 to 12 minutes until the edges are brown, but the centers are slightly undone.
Cool the cookies on the baking sheet for 5 minutes. Then, transfer them to a wire cooling rack to cool completely.
Cream Cheese Frosting
Beat the cream cheese and butter for 1 to 2 minutes.
Slowly add the remaining ingredients and mix until smooth.
Place half of the cookies flat side up. Pipe frosting onto each cookie. Then, place the other cookies on top. Enjoy!
Notes
Filling: Make sure your cookies are cooled completely before adding the cream cheese filling. Butter: Be certain the ¼ cup melted butter is not steaming hot when mixing. Cream Cheese: 4 ounces cream cheese should be room temperature before mixing otherwise it will be clumpy. Carrots: Make sure the grated carrots are small enough therefore they bake properly.