In a separate bowl, combine the rye flour, white flour, baking powder, salt and cocoa powder. Stir with a fork or whisk to remove any lumps. Add this all to the bowl of beaten eggs and fold together gently using a spatula until just combined.

Pour the batter into the prepared tin and spread out gently into an even layer. Bake for 12-15 minutes until puffed and pale on top. Run a knife around the edges to loosen the cake from the tin as needed.

Dust a clean tea towel with icing sugar and flip the cooked cake out onto it. Trim off the very edges of the cake (they’re crusty so don’t roll well) using a pair of scissors or a sharp knife. Gently peel away the baking paper then, starting at a short edge, roll the cake up with the tea towel (almost as if the tea towel is the filling of the cake). Leave the rolled cake seam side down to cool completely at room temperature.

Once the cake has cooled, make the filling by whipping the cream until billowy but still forming soft peaks. Fold in the melted chocolate (make sure it has cooled a bit before folding in) followed by the amaretto.

Make the ganache by heating the cream in a small pot until gently steaming. Place the chopped milk chocolate into a small heatproof bowl and pour the steaming cream over the top. Let sit for 5 minutes so the chocolate can melt then stir together until completely smooth. Set aside at room temperature so it can thicken slightly – you want it to be the texture of a thick glaze so it’s still pourable but not super runny.

Carefully unroll the cooled cake and spread the filling all over the surface of the cake. Re-roll the cake and place onto a wire rack set over a baking tray.

Pour the cooled ganache over the cake and leave so that the excess glaze drips off onto the tray below. Once the glaze has stopped dripping, use a metal spatula to transfer the cake to a serving platter. You can serve it now or chill for up to 24 hours before serving.