Combine the coffee with the sugar and Baileys, leave to cool. Pour the liquid into a shallow container to a depth of approx. 2 cm, freeze for approx. 2 hrs., scraping the ice crystals off the edges of the container 3 or 4 times during freezing and stirring them in.
In a wide-bottomed pan, toast the nuts over a medium heat. Add the sugar, continue toasting, shaking the pan occasionally until all the sugar has melted. Remove the pan from the heat, mix using a wooden spoon. Transfer immediately to a sheet of baking paper, smooth down and leave to cool. Pour the cream into the remaining caramel in the pan, bring to the boil, reduce the heat and simmer for approx. 2 mins. Break up the caramelized nuts with a rolling pin. Add to the cream shortly before serving and heat gently.