2kg/4陆lbs dessert apples, about 12, peeled
100驳/3陆辞锄 caster sugar
60g/2陆oz cold unsalted butter, diced
30g/1oz unsalted butter, melted, to add richness
300g/11oz all-butter puff pastry, rolled to a thickness of 3mm/鈪沬n, cut very slightly larger than the diameter of the tarte tin, pricked with a fork and frozen