Grease a
25cm/10in tart tin. For the pastry, sift the
flour, cocoa powder, icing sugar and salt into a
bowl. Set aside.
Melt the
butter and water over a low heat. Pour over the
flour mixture and stir until the dough is
smooth.
Press the dough
evenly over the base and sides of the tart tin.
Chill while preparing the filling.
Preheat a baking
sheet in the oven at 190'C/375"F/Gas 5. Whisk the
sugar and eggs until the sugar is dissolved. Add the
lemon rind and juice and mix well. Add the cream.
Pour the filling
into the pastry case and bake on the hot baking
sheet until the filling is set, 20-25 minutes.
Cool on a wire rack, then decorate with chocolate
curls.