Step 1: Preheat the oven

Preheat your oven to 200°C (180°C fan). Grease and line a Swiss roll tin with baking paper, ensuring it fits snugly in the tin.

Step 2: Make the chocolate sponge

In a large mixing bowl, whisk the eggs and caster sugar together using an electric mixer until the mixture is light, pale, and thick, about 5-7 minutes. Sift in the self-raising flour and cocoa powder, then gently fold them into the egg mixture with a spatula, being careful not to knock out the air.

Step 3: Bake the sponge

Pour the batter into the prepared Swiss roll tin, spreading it evenly. Bake in the preheated oven for 8-10 minutes, or until the sponge is just firm to the touch.

Step 4: Roll the sponge

While the sponge is baking, place a sheet of baking paper on your work surface and dust it with icing sugar. Once the sponge is done, turn it out onto the prepared paper while it’s still hot. Peel off the lining paper from the sponge and, starting from one short end, roll the sponge up with the sugared baking paper inside. Leave it rolled up to cool completely – this will help it hold its shape later.

Step 5: Make the chocolate buttercream

In a mixing bowl, beat the softened butter until smooth. Gradually add the sifted icing sugar and cocoa powder, beating until well combined. Add 1-2 tablespoons of milk as needed to achieve a smooth, spreadable consistency.

Step 6: Fill and roll the cake

Once the sponge has cooled, carefully unroll it and remove the baking paper. Spread a thin layer of chocolate buttercream over the entire surface. Re-roll the sponge carefully but firmly to keep its shape.

Step 7: Cover with buttercream

Spread the remaining buttercream evenly over the top and sides of the log. Use a fork to create bark-like lines in the buttercream, making it resemble a Yule log.

Step 8: Dust with icing sugar

Lightly dust the finished Yule log with icing sugar for a festive, snowy effect.