Method

• 1.
  Preheat oven to 200°C.
• 2.
  Place 200g caster sugar and 200ml white wine in a large saucepan and stir to dissolve the sugar. Add the peaches and enough water to just cover them, then poach the peaches over low heat until just tender (this will depend on the ripeness of the fruit). Drain, then set aside to cool. (Reserve poaching liquid and use at a later stage to poach other fruits; the liquid will keep in the fridge for up to 2 weeks.) Peel and slice the peaches, discard the stone and place the peaches in six ovenproof gratin dishes.
• 3.
  Place the egg yolks in a bowl with the remaining sugar and wine, and the marsala, then whisk the mixture until pale and fluffy. Place the bowl over a saucepan of simmering water and continue whisking (an electric whisk is great for this job) until the mixture is thick and pale. Divide the mixture between the gratin dishes, spreading over the fruit, then bake in the oven for 12-15 minutes until the top is light golden.
• 4.
  While it's warm, dust the peach gratin with icing sugar and serve with scoops of ice-cream.