Beat together the butter and sugar until fluffy.
Add the eggs then flour, baking powder and salt, pulling together a rough dough. Divide into two circles.
Preheat the oven to 180ºc.
Roll out the pastry into two thick circles between 22cm and 24cm.
Spread a layer of pear jam on the bottom circle.
Arrange the thinly sliced soft pear slices on top of the jam.
Place the second circle on top.
Bake for 30 minutes at 180ºc.
Serve luke warm or cold with creme fraiche.