Preheat the oven to 350ºF. Line the bottom of an 8-inch round cake pan with a circle of parchment paper. Grease the bottom and sides of the pan.

In a large bowl, whisk together the almond flour, arrowroot flour, sugar, coconut flour, cinnamon, ginger, nutmeg, baking powder, baking soda, and salt. In a separate bowl, whisk together the pumpkin, eggs, coconut oil, maple syrup, molasses, and vinegar. Pour the wet ingredients into the dry and stir to combine thoroughly. Pour into the prepared pan. Bake for 30-40 minutes or until a toothpick inserted into the center comes out clean. Cool completely.

Cover the cashews with boiling water and soak for 15-30 minutes. Drain and transfer to a food processor fitted with the steel blade. Add the maple syrup, milk, and salt. Process until smooth and creamy, 3-5 minutes, stopping to scrape down the sides of the bowl as needed.

In a bowl, combine all the ingredients for the topping, except the mint leaves. Spread the frosting over the top of the cake, using as much or as little as desired. (Leave the sides of the cake bare.) Pile the apple topping onto the top of the cake. Garnish with mint leaves, if desired. Serve immediately.