Preheat the oven to 180°C / 350°F and line one baking sheet with parchment paper.

Whisk 4 eggs, 100 g granulated sugar, and 1 tsp vanilla flavoring for 10 minutes until pale and voluminous.

Sift 90 g all-purpose flour with 30 g unsweetened cocoa powder.

Fold the flour and cocoa mixture into the egg mixture in three additions using a rubber spatula.

Spread the batter evenly on the lined baking sheet.

Bake the sponge for 10 to 12 minutes at 180°C / 350°F.

Turn the hot sponge onto a clean kitchen towel and remove the parchment paper.

Roll the sponge in the kitchen towel and let it cool completely.

Whip 500 g mascarpone, 250 ml heavy cream, and 100 g powdered sugar until thick and spreadable.

Fold 2 tbsp Nutella into the mascarpone cream until evenly combined.

Finely chop the Oreo cookies.

Unroll the cooled sponge and spread the Nutella mascarpone cream evenly over its surface.

Scatter the chopped Oreo cookies over the cream.

Roll the sponge tightly into a log and wrap it in plastic wrap.

Chill the rolled log for 60 minutes.

Melt 200 g dark chocolate with 200 ml heavy cream in a saucepan over low heat.

Stir 2 tbsp neutral oil into the melted chocolate glaze until smooth.

Let the chocolate glaze cool until it is thick enough to coat the log.

Cover the chilled log completely with the chocolate glaze.

Decorate the Yule log as desired and chill it for at least 60 minutes before serving.