Preheat the oven to 350°F. Line an 8x8-inch square or round cake pan with parchment paper, making sure the paper covers the bottom and sides of the pan.
In a large bowl, mix together the almond flour, cassava flour, cinnamon, baking soda and salt.
Place the yolk of the eggs in a large bowl and reserve the egg whites in a separate large bowl. Mix the egg yolks with the pumpkin puree, coconut oil, apple sauce, vanilla and coconut sugar until combined.
Using a spatula, mix the wet and dry ingredients together just until combined. Do not over mix.
Using an electric or stand mixer, whip the egg whites until it forms stiff peaks. Mix the whipped eggs gently with a spoon into the batter until everything is just combined. Do not overwork your batter.
Spread batter into the prepared pan and bake for 40 minutes, or until a toothpick inserted into the center of the cake comes out clean. Set pan on a cooling rack to cool. After about 20 minutes remove cake from pan and let it continue to cool on the rack.