1Preheat oven to 200 C (180 C fan-forced). Line oven tray with baking paper.
2Place two pastry sheets on clean board; brush lightly with a third of the butter. Top with two more pastry sheets; brush lightly with half of the remaining butter. Repeat layering with remaining pastry and butter.
3Fold pastry in half to form a square; cut 22 cm-diameter circle from pastry square. Arrange peach slices on pastry circle; sprinkle with sugar.
4Bake about 20 mins or until galette browns. Serve warm galette brushed with jam.
1. Cover the pastry with greaseproof paper then a damp towel when you are working with it, to prevent it drying out.
2. Nectarines, apricots, apples, plums and pears are all suitable fruits to use in place of the peaches.