Preheat the oven to 230°C. Sift the flour. Then, in a large bowl, beat the 5 whole eggs, almond flour and sugar together. In a separate bowl, whip the egg whites with the confectioners’ sugar, adding the sugar a little at a time. Alternate the egg mixture with the flour, making 3 additions of flour and 2 of egg whites.
Scoop a small amount of batter into a small bowl. Then, mix in the butter, and return the batter to the large bowl. Divide the batter between two 15 x 10-inch rimmed baking trays lined with baking paper, and bake for 6–8 minutes or until golden brown.
Remove the trays from the oven and allow the cakes to cool for about 2 minutes or until cool enough to handle. Loosen edges of 1 cake with a knife and turn upside down onto a clean, flour-dusted tea towel. Starting at one corner, carefully peel off the paper. Starting at one short side, roll up the cake in the tea towel and let it cool completely on a rack. Repeat with the remaining cake.
Unroll each cake and spread evenly with half of the chocolate spread. Reroll and place each roll, seam side down, on a platter. Spread the remaining chocolate spread over the rolls. Cut off the edges to expose layers of cake and filling. Decorate as desired, and your delicious creation is ready to impress!