Karine Zablit's all-chocolate yule log (bûche)

The hazelnuts

1. Preheat the oven to 180 °C.
2. Place the hazelnuts on a baking sheet and bake for 15 minutes, keeping an eye on them.
3. Allow the skins to crack and the hazelnuts to toast. Remove from the oven and let cool.
4. Peel the hazelnuts and chop them coarsely.

The Viennese cocoa sponge cake

1. Beat the eggs and sugar together with an electric mixer for 10 minutes until the mixture is light and fluffy.
2. Sift the cocoa and flour together and gently fold them into the egg/sugar mixture with a spatula.
3. Spread the batter on a greased 42 x 35 cm silicone mat or on a baking sheet lined with parchment paper.
4. Bake for 10 minutes.

The ganache

1. Bring the cream to a boil and pour it over the chocolate.
2. Gently mix with a spatula until smooth and glossy.
3. Refrigerate for 20 minutes.
4. Spread three-quarters of the ganache over the Viennese sponge, sprinkle with toasted hazelnut pieces.
5. Set aside the remaining ganache for decoration.
6. Roll the sponge up from the short side (35 cm).

Decoration

1. Spread the remaining ganache over the rolled yule bûche, trim both ends for clean edges, and decorate with hazelnut pieces.