Whisk the egg whites into a lush foam, add the erythritol and continue whisking until stiff peaks. Carefully add the almond flour in several batches to the resulting meringue.
Divide the batter into 2 portions (about 110-115 grams each) and place them on the bottom of a mold or parchment. Bake at 140-170°C (depending on your oven) for 10-15 minutes until lightly golden.
Take the finished cakes out of the oven and let them cool slightly without turning them over. Take them out and cool them completely. It is great to let them sit for a longer time (a few hours) so that a crust forms on them.
While the cakes are cooling, make the cream. Pour the cream into a heavy-bottomed pan and add the erythritol. Place it over low heat and warm it up until the erythritol has dissolved. Pour some of the cream into the bowl with the egg yolks, stir well, and pour back into the main cream mass. Continue heating the cream, stirring constantly (well on both sides and bottom) with a whisk. Once the cream has thickened, remove it from the heat and, without stopping to stir, add the butter (75 g). Stir until the butter is completely dissolved (add vanilla extract in the process).
Crush the dried cakes (preferably by hand, to control the size of the crumbs), mix with the cocoa, add the cream and the pre-melted butter (40 g). Knead the mixture thoroughly.
Put the mass on plastic wrap, shape it into a salami and place it in the freezer for 20-30 minutes to harden it. Then store it in the refrigerator.