-
Preheat the oven to 350°F/180°C.
-
Prepare the cocoa
sponge cake: separate the egg whites from the yolks.
Whisk the whites to stiff peaks with the sugar and the
lemon juice, and then blend in the yolks quickly. Mix.
Fold the cocoa in gently with a spatula.
-
Roll out the
dough on a baking sheet covered with baking paper,
rolling to a 1/4 inch (5 mm) thickness. Bake for
about 12 minutes.
-
Take the sponge cake out of the oven
and allow it to cool.
-
Prepare the ganache: grate the
chocolate into a bowl. Bring the cream to a boil and add
the chocolate. Mix, smooth, and store in a cool place.
-
Pour 3/4 of the ganache over the sponge cake
and smooth it out carefully with a spatula. Roll up the
sponge cake and chill for 20
-
30 minutes.
-
Take the roll out of the fridge. Using the
remaining ganache, cover the ends of the log. To imitate
a
tree
trunk, score the surface with a fork. Decorate according
to taste.