Preheat oven to 325º F. Soak the raw cashews for the frosting now: add cashews to a large measuring cup and cover with hot water. Set aside.
Prepare 3 9-inch cake pans: grease the bottom and sides of each with coconut oil. Line the bottom of each pan with a round of parchment paper. See note 3 for more information.
In a large bowl, whisk together dry ingredients: almond flour through salt. In a medium bowl, whisk together wet ingredients until very smooth: eggs through almond extract. Gently stir wet ingredients into dry and whisk until very smooth.
Divide cake batter evenly among prepared cake pans. Bake 15 minutes, then swap position of cake pans in oven. Switch oven racks and left to right (Move pans on the lower rack to the higher rack and pans on the left to the right, etc.). Bake another 10-12 minutes or until a toothpick comes out clean. Remove from oven and let rest 5 minutes.
Place an upside-down plate on top of cakes and carefully invert; cake should come right out. Cool completely or wrap in plastic wrap and freeze until frozen solid, about 3 hours. See note 4 for more information.
While cakes are baking, make frosting: in a high-speed blender, blend together all ingredients until very, very smooth. Taste and add additional maple syrup for sweetness, lemon zest for tang, or apple cider vinegar for a sour taste. Pour into a large bowl and place in freezer. Optionally, after 30 minutes, remove from freezer and whip on high speed for 2 minutes. Return to freezer, freeze another 30 minutes, remove, and whip on high speed for 2 minutes. Return to freezer and freeze until super thick, about 2-2 1/2 total hours. You can skip whipping the frosting, but doing so creates a lighter, airier frosting, and it's very worth it!
Frosting is ready when, if you tilt the bowl, the mixture does not move at all.
When ready to frost the cakes, pull all items out of freezer, if chilled. With a serrated knife, cut off any domes of the cakes to make them perfectly flat and even; reserve domes for decoration. Frost cake with a spatula, frosting with a thin layer over the top layer and sides to start. After this crumb coat is completed, place cake in refrigerator for 30 minutes. Remove from fridge and finish with a top coat. This will keep the top coat more pure and smooth.
Crumble cut-off domes into red velvet crumbs. Decorate cake with crumbs, cut into slices, and serve. This cake will keep at room temperature for several hours, but the frosting holds a little better in the refrigerator.