Melt the butter and dark chocolate.
Fit the K beater to the machine.
Line the round tin with parchment paper.
Add Ingredients 1 (butter, sugar, syrup, cocoa powder) into the Mixer bowl.
Attach the Mixer bowl to the machine and fit the splash guard.
Mix on speed Min for 30 seconds.
Add Ingredients 2 (biscuits, raisins) to the bowl.
Add Ingredients 3 (chocolate) into the Mixer bowl.
Transfer the contents of the Mixer bowl to the round tin and level.
Chill in the fridge for 1 hour.
Cut into slices.
Serve.