Pre heat oven to 375 degrees.

Grease a 15" x 10" x 1" rimmed baking sheet. Line with parchment paper: butter and flour the paper.

In a large mixing bowl, beat egg yolks until thick and pale yellow. Add 1/3 cup sugar, beat well until sugar dissolves. Add water and vanilla. Fold in ground almonds, cake flour and cocoa. Set aside.

Beat egg whites in the bowl of a stand mixer until foamy. Add cream of tartar and salt. Beat until stiff peaks are formed. Add remianing 1/3 cup sugar. Fold into almond flour mixture taking care not to deflate the batter.

Spread batter evenly onto the baking sheet. Bake at 375 for 10 minutes or until top springs back when touched. While the cake bakes, line a 15 x 10 inch clean dish towel with 2-3 TBSP sifted powder sugar. Flour sack dish towels work grea .

When cake is done, immediately loosen the sides from the pan with a sharp knife. Invert the cake onto the sugared dish towel. Peel off the parchemnt. Roll up the cake from the short end with the towel in place. Cool completely on a wire rack for 30 minutes while you make the filling or the frosting.

Unroll the cake, remove the towel. Spread the cake with the whipped filling leaving a one inch gap around the edges. Roll the cake back up into a log. Cut a 2" diagonal slice from the end of the cake. Place entire cake on a serving paltter and tuck strips of pachment paper aroud the edges to collect excess frosting and protect the platter while decorating. Position the slice of "cut side cake" onto the side of the remianing log to resemble a tree knot or a branch.

Spread the chocolate buttecream frosting all over the cake and tree knot. Chill for 15-30 minutes. With a fork or an offset spatula create bark lines in the frosting. Garnish the cake with toadstools made of meringue, or chocolate truffles or chocolate shavings and greenery. Remove the parchments strips.

Chill the cake for 2 hours or up to 2 days. Let the cake sit at room temperature for 30 minutes before slicing. Dust with powdered sugar before slicing so the yule log looks as though it has been in the snow and resting in a forest.

Pour whipping cream into the bowl of a stand mixer. Add coffee granules and let rest for a few minutes. Combine powdered sugar and cocoa.

Beat the whipping cream until frothy, gradually adding the powdered sugar mixture. Beat until stiff peaks form. Chill for 30 minutes before using as a filling for your cake.

Chop Chocolate and place in a heat proof bowl over a simmering pan of water. Stir with a silacone spatula until melted. Set bowl aside to let chocolate cool to room temperature.

In the bowl of a stand mixer, beat butter until fluffy and pale. Add in egg yolk and vanilla and beat 1-2 minutes more. Turn mixer to low and slowly add in the powdered sugar and coffee until creamy and light. Mix in the cooled chocolate on low.

Do not overmix or whip the frosting further. If fosting does not set, the butter may be too warm. Set in fridge for 5 minutes until frosting is spreadable, thick and creamy.