Combine the chocolate, cream and milk in a small non-stick pan over a low heat for 4-5 minutes until melted, then whisk until smooth.
Next, put the chestnut purée in a food processor and blend until smooth. Pour in the warm chocolate mixture, then add the egg, Lyle's Golden Syrup®, coffee liqueur or brandy and process again. Scrape down the sides. Add the amaretti biscuits and pulse once, just enough to combine.
Divide the mixture between 6 small pots, cover and chill in the fridge until firmed up, for about 3-4 hours.
In a small bowl mash the chestnut purée with the back of a teaspoon until fairly smooth, then stir in the Lyle's Golden Syrup®. Lightly whip the cream until soft peaks form and marble in the chestnut mixture. Divide between the chocolate pots, arrange the marrons glacées on top, then drizzle over a little Lyle's Golden Syrup® and serve.
Recipe courtesy of Lyle's Golden Syrup®