Preheat the oven to 160°C and line a Swiss roll tin with parchment, with excess parchment to hang over the ends and sides of the tin.
Separate the egg whites from the egg yolks into 2 bowls.
Whisk the egg yolks and 90g of sugar until fluffy and pale in colour or ribbon stage. Add the vanilla, then sieve in the cocoa and milo over the yolk mixture and fold them in.
In the second bowl, whisk the egg whites and 50g of sugar until stiff peak. Test for stiff peak by lifting the whisk from the whites and see if a peak forms.
Add in a few spoons of the whites into the yolk mixture and fold them in with gently to loosen the mixture without breaking it.
Next, add the remaining whites in three intervals, folding carefully to avoid losing the air.
Pour the batter onto the Swiss roll tin and bake in the oven for 20 minutes.
Step 2- Prepare the frosting and cake filling
For the frosting, heat the cream and pour over the chocolate. Let the heat of the cream melt the chocolate for 2 minutes and mix well. Once cool, chill it in the freezer for 7 minutes then bring out to whisk until it is fluffy.
For the filling, whip the cream until soft peak and set aside.
Step 3- Prepare the Swiss Roll
Prepare a second piece of parchment and sieve icing sugar over it.
Let the cake cool a little before turning it out onto the second piece of parchment and icing sugar.
Step 4- Roll the cake
Trim the edges of the cake so that it is even and spread some of the whipped cream thinly over the sponge, going right out to the edge.
Roll the cake from the long side or length of the cake. Take care to get a tight roll from the beginning and roll up the whole cake. Press against the parchment, rather than the cake, for an easier roll.
Cut off the ends at a diagonal angle, wrap the cake in parchment and chill it in the fridge.
Step 5- Decorate the log cake
Create branches by cutting pieces off the log diagonally and placing the cut side onto the log as desired. Spread some frosting onto the cut end to hold the branches in place. You may leave the log as it is also.
Spread the frosting over the log, covering the cut-off ends as well as any branches. Create a wood texture by lightly dragging a fork through the frosting. Use the fork to draw wobbly circles, like tree rings, on each end of the log.
Dust the log generously with the milo powder, followed by light dusting of icing sugar.