Caramelise the sugar in a pan and pour into the moulds. Break up the marrons glacés and distribute evenly between the moulds.
Peel and core the pears, cut in half and thinly slice. Place one sliced pear half face down in each mould with the slices arranged at a slight angle. Cover the moulds with the puff pastry and cut off the excess pastry.
Bake in oven at 180°C for approximately 20 minutes. Turn the tarte tatins upside down to serve and sprinkle with icing sugar.
