Place the
flours, hazelnuts, sugar, salt and butter in a food processor and
process in short bursts until the mixture resembles breadcrumbs. Add
30-45ml cold water and process until the dough comes together. Turn out
on to a lightly floured surface and knead gently until smooth. Roll out
and line a 25cm or 10" flat tin. Be sure not to stretch the pastry and
gently ease it into the corners. Chill for 20 minutes. Preheat the oven
to 375F or Gas 5.
Line the
pastry with greaseproof paper and fill with baking beans or bread
crusts. Bake blind for 15 minutes, remove the paper and continue for a
further 5-10 minutes, until the pastry is crisp. Allow to cool. Whisk
the lemon curd into the cream or fromage frais and spread over the base
of the pastry. Arrange the orange slices on top and serve at room
temperature.