To make the pastry, place the walnuts in a food processor and finely chop. Add the flour and icing sugar and pulse to blend together. Add the butter and mix to give a breadcrumb texture, add 2-3 tbsp cold water and mix to give a soft dough. Wrap in clingfilm and chill for 15 minutes.
Roll the pastry out on a floured surface and line a 23cm fluted flan tin. Prick the base with a fork and chill for 10 minutes. Place on a baking tray, line the pastry case with foil and add baking beans. Bake for 10 minutes, remove the beans and foil and cook for a further 5 minutes.
Meanwhile, to make the filling, whisk together the sugar and butter until blended. Whisk in the eggs, one at a time then whisk in the vanilla, maple syrup and cream.
Roughly chop 100g of the walnuts and add to the filling with the cranberries. Pour into the pastry case and scatter over the remaining walnuts. Bake for 10 minutes then reduce the oven temperature to 180oC, gas mark 4 and bake for a further 20 minutes until just set. Allow to cool slightly before removing from the tin.
Notes
Salt: 0.07gCooks tip:Great served warm with ice cream or cream. Try using golden syrup instead of maple syrup.