It comes from a leaflet I picked up somewhere, several years ago, when we were in Alsace, and I've made it many times since.
Preheat oven 190C/gas5
You need a large fluted and greased flan tin [preferably with a loose bottom] - 24-26cm.
For the pastry : 170g flour, 1 tbspn caster sugar, pinch salt, 125g cold butter cut into cubes and 2 tbspn cold water.
Rub the butter into the flour to which the sugar and salt have been added. Add the water and make into a ball. Cover in clingfilm and put into the fridge for about an hour.
Roll into a circle, and use the rolling pin to fit the pastry into the flan tin.
For the filling:
You need 4 apples - I used Granny Smith, but you could use Golden Delicious or Braeburn, but not Bramleys, as they don't hold their shape. Peel and cut them into quarters, take out the core and pips and slice them carefully into neat slices. Spread them out evenly over the pastry.
Beat 1 whole egg and 1 yolk in a bowl with 6 tbspn sugar, 20cl of double cream or crème fraîche and 1 tspn vanilla extract. Pour this over the apples and bake for 50-55 mins till golden.
You can, of course, use your favourite recipe for shortcrust pastry with a little sugar added. I like the textures of this tart - the crunchy pastry, the soft fruit mixed with a lovely creamy layer.
I have made it with Bramleys, just to try them, and they became mushy instead of keeping the pretty slices.