Preheat the oven to 325ºF. Line two 6 inch cake pans with a parchment paper circle cut to fit the bottom of the pan, and grease the sides with melted butter or a cooking spray.
In a large bowl, combine the wet ingredients until smooth: eggs, ghee, apple sauce, coconut sugar or maple syrup, sweet potato, and vanilla.
In a medium bowl, combine the dry ingredients: almond flour, coconut flour, spices, salt, and baking soda.
Add the dry ingredients to the wet 1/3 at a time, stirring until just combined.
Transfer the cake batter to the lined cake pans and bake for 30 to 40 minutes, or until they have risen and are golden on top, and a toothpick inserted to the center comes out clean. The cakes will only jiggle slightly when baked through.
Allow the cakes to cool completely, then remove from the pans and wrap in plastic wrap. Transfer to the refrigerator until chilled, so it's easy to slice the tops off. Make your frosting while the cakes cool (see below).
Lay the cold cakes out on a flat surface, and use a large serrated bread knife to slice the tops off so you have an even surface. Lay one cake on a turntable or decorating plate with the cut side up, and layer about 1/4" to 1/2" thick of frosting on top. Sandwich the other cut cake on top, with the cut side facing down. This will leave you with a smooth cake surface on top.
Use a frosting spatula to get a thin layer of frosting onto the cake, just enough to "seal in" the crumbs (I didn't do this step for Hudson's cake so it left me with some crumbs in the frosting! This is how you avoid that!)Transfer the cake to the refrigerator with the first thin layer of frosting until chilled, about 30 minutes. Continue frosting the cake with a thicker layer of frosting this time. Use your turntable and frosting spatula to get an even, thick layer, and keep smoothing until you're satisfied (I looked up tips for cake frosting on YouTube!)
Once your cake is frosted, transfer to the fridge to cool and allow the frosting to set & slightly harden. Bring the cake out about 30 minutes before serving to bring it to room temperature. Enjoy!