Blanch 500g fresh chestnuts in boiling water for 4 minutes, drain, then peel while still warm.
Bring 300g caster sugar and 300ml water to the boil in a heavy-based pan to make a syrup.
Simmer for 10 minutes, then add the chestnuts and simmer for 7-8 minutes.
Take off the heat and leave to stand overnight in the syrup.
The next day, bring the chestnuts/syrup back to the boil, cook for 1 minute, then remove from the heat and cool.
Repeat the boiling and cooling process 2 or 3 times over the next couple of days until all the syrup is absorbed.
Preheat the oven to around 70°C, spread the candied chestnuts on a tray covered with baking paper, then pop into the oven.
Prop open the door and leave for 2 hours or until firm.
