Preheat oven to 180°C (350°F).
Beat egg yolks with sugar until pale and fluffy.
Add flour and milk, mixing well, then stir in cocoa powder.
In a separate bowl, beat egg whites until stiff peaks form. Gently fold into the batter using a spatula.
Pour the mixture into a rectangular pan lined with parchment paper. Bake for 12–15 minutes.
2. Make the Cream Filling:
Beat softened butter until creamy, then add liquid cream.
Add icing sugar and beat again.
Melt dark chocolate over a bain-marie and fold it into the butter mixture until smooth.
3. Prepare the Glaze:
Melt chocolate over a bain-marie.
Add icing sugar and mix until smooth.
4. Assemble the Roll:
Remove the cake from the oven and place it on a damp kitchen cloth sprinkled with a couple tablespoons of sugar.
Spread the chocolate cream evenly over the cake.
Carefully roll the cake into a log, trimming the ends for a neat finish.
Allow to cool completely, then pour over the chocolate glaze to coat the roll.
