Either finely chop or grate the chocolate into a mixing bowl
Bring cream to a light simmer from low heat
Pour cream, espresso and vanilla extract over the chocolate pieces and mix until combined and smooth
Transfer chocolate mixture to a wide dish and place in the fridge to set for 2 hours
Scoop out 1 tbsp of the mixture and roll with your hands until round, add to a plate and put back in the fridge for another hour to set shape
Remove from fridge and roll with your hands again to smoothen the ball’s surface
Roll in a mixture of 2 tbsp of cocoa powder and the coffee grind from the Nespresso capsule