Line a baking tray with non-stick paper. Break the chocolate into small pieces and place in a bowl along with the butter and Baileys.
Pour the cream into a small saucepan and heat until it's just at boiling point. Remove from the heat and stir into the bowl of chocolate that has the butter and Baileys. Continue stirring until the chocolate has melted and the mixture is smooth. Leave to cool in the fridge for 2-3 hours, or until firm enough to work with.
Remove the truffle mixture from the fridge about 20 - 30 minutes before you intend to use it. Using a teaspoon, scoop the mixture onto the lined baking sheet.
Wearing disposable gloves, roll the truffle mixture between your palms to get a more rounded shape. Toss in cocoa powder and return to the lined baing tray.
When all the truffles are made, place them back in the fridge for a couple of hours before packing them into cellophane gift bags or chocolate boxes.