Technical Stages :

• Cook the chestnuts 20 minutes in boiling salted water.
• When cooked, drain them and peel them.
• Pass them through the food mill.
• Blanch the softened butter along with caster sugar.
• Add the melted dark chocolate, chestnut purée, candied chestnuts broken in pieces, 1 teaspoon of vanilla extract and 2 tablespoons of Cognac.
• Pour this preparation into a square mold that is lined with plastic wrap.
• Leave to harden in the fridge for 12 hours minimum before serving.