First, pre-heat the oven to 350F.
Grease a 9-inch baking pan with cooking spray or coconut oil.
Then, place a piece of parchment paper on the bottom of the cake pan, leaving an overhang on the sides to lift the cake out when it’s done. Set aside. If you have a removable bottom baking pan, you can skip this step.
In a large bowl, whisk together the egg yolks and 1/2 cup of natural sweetener xylitol for about 1 minute or until the yolks become pale in color.
Add the vanilla extract and salt. Whisk to combine everything well. Set aside.
In the bowl of a standard electric mixer fitted with the whisk attachment, beat the egg whites at medium speed for about 1 minute. Sprinkle in the remaining 2 tablespoons of natural sweetener xylitol, and continue to beat the egg whites until they are very white, firm and fluffy. The eggs whites will be ready when you turn the bowl upside down and the egg whites don’t fall out.
Add half of the egg whites to the egg yolk mixture and mix to combine.
Add the remaining egg whites over the yolks, half of the almond flour, and cocoa powder.
Gently fold them into the yolks.
Add the remaining almond flour and fold until you have a homogeneous batter.
Carefully pour the batter into the prepared pan.
Bake the cake for about 30-40 minutes. The cake will be ready when it is golden brown and when a toothpick is inserted in the center and comes out clean. Let the hot cake cool on a wire rack for 5 minutes before removing it from the pan.
While the cake is in the oven, make the chocolate frosting.
In a heatproof bowl, add dark chocolate over simmering water.
When the chocolate is starting to melt, add the almond milk and mix well until all is combined and smooth.
Allow the chocolate frosting to cool before icing the cake.
Spread the frosting chocolate over the top and add some almond slices. Enjoy!