Peel and core the quinces and cut them into small cubes. Boil them with a little water, sugar and lemon juice until soft and puree them. The puree should not be too liquid - thicken with some cornstarch if necessary.
Place the puff pastry on a baking tray, dab with a fork. Pre-bake the puff pastry for a few minutes. Then spread the quince puree evenly on top.
Peel the apples and cut them into thin slices. Spread evenly on the quince jam and sprinkle with icing sugar and cinnamon. Spread butter flakes on top.
Bake at 180 degrees for 20-25 minutes. If necessary, roast the tart a little more under the grill. Remove from the pan, quarter it and serve lukewarm with a scoop of vanilla ice cream.