Roll out the pastry on a lightly floured work surface and use it to line a 20cm/8-inch loose-bottomed quiche or flan tin, reserving the pastry trimmings. Prick the base of the pastry with a fork and leave to chill in the refrigerator for 30 minutes.
Mix the syrup, coconut, double cream, grated lemon and lemon juice together in a bowl.
Pour the mixture into the pastry case and decorate the tart with a lattice pattern from the pastry cuttings if you wish.
Bake in a preheated oven, 190C/375F for about 35-40 minutes, or until the filling is just set and looks golden brown.
Leave the tart to cool slightly in the tin, then serve.