1. Preheat your oven and prepare a baking sheet with parchment paper.
2. Whisk eggs and sugar until pale and fluffy.
3. Sift cocoa powder and flour, then gently fold into the egg mixture.
4. Pour the batter onto the baking sheet and spread evenly.
5. Bake in the oven until the sponge is set but still soft.
6. While warm, roll the sponge in a clean kitchen towel to form shape.
7. Let the rolled sponge cool completely before unrolling.
8. Whip the cream with sugar until soft peaks form.
9. Mix cherry jam or compote with brandy for the filling.
10. Gently unroll the sponge and spread the cherry-brandy mixture.
11. Spread whipped cream evenly over the cherry filling.
12. Carefully roll the cake back into a log shape.
13. Prepare a chocolate ganache or buttercream for exterior frosting.
14. Cover the log with the frosting, smoothing it evenly.
15. Use a fork or spatula to create a bark-like texture.
16. Optionally, cut off a small section and attach it to make a branch.
17. Dust with cocoa powder or powdered sugar for a snowy effect.
18. Decorate with cherries, edible decorations, or meringue mushrooms.
19. Refrigerate for a few hours to set the flavors.
20. Serve as a festive centerpiece dessert for Christmas dinner.