Place the tempered chocolate into a hemisphere mould and spread it out so that it covers the edges.
Turn the mould upside down and shake to let any excess drip out. Flip it back over and use a spatula to flatten the edges.
Flip back upside down and leave over some parchment paper to set.
Ensure the moulds have only a thin coating of chocolate - this will help them melt easier when served.
For the chocolate cremeux:
Add the milk chocolate and leftover dark chocolate to a bowl.
Mix the sugar and egg yolks together with a fork.
Pour the cream into a saucepan and beat until just starts to boil.
Add a little of the cream to the egg yolks together mixture and stir in.
Tip the egg mixture back into the cream and stir in over the heat. Heat it until reaches 85°C. Do not overheat or it will split.
Pour through a sieve onto the chocolate.
Stir together until it becomes a smooth custard.
Let cool until it comes to room temperature.
For the caramel sauce:
Put the cream, butter and brown sugar into a bowl and stir.
Microwave on high heat for two minutes and stir again.
Keep giving 1 minute microwave bursts and storing until it’s hot and thickened.
Assembly:
Place a chocolate hemisphere on a plate and fill with refrigerated chocolate cremaux.
Take another hemisphere and press to the base of a warmed pan to slightly melt the edge and place onto the bottom hemisphere. Smooth the edges with a spatula knife.
To serve, make sure the spheres are at room temperature and the caramel is hot to ensure a good show. Pour over the hot caramel sauce and admire the magic!