For the pastry dough:
For the tart:
Make the pastry dough: In a food processor, pulse together flour, sugar, and salt. Add in butter and pulse until mixture resembles coarse meal with some small butter lumps remaining. Beat together yolk and water with a fork and add into flour mixture until combined well.
Turn out dough onto a lightly floured surface and knead gently until dough forms. Form dough into a ball, then flatten into a 5 inch disk. Wrap dough tightly in plastic wrap, and chill at least 1 hour. Dough can be prepared up to 2 days ahead.
Make the tart: Roll out dough into a 13 inch round (about 1/8 inch thick) on a floured surface fit into a 10 inch tart pan with a removable bottom (note: we divided the recipe between 2 rectangular tart pans instead). Trim edges of dough. Lightly poke the bottom of the tart shell all over with a fork, then chill for half an hour.
While dough is chilling, preheat oven to 425 F. Remove chilled dough from fridge, line with foil and pie weights, and bake for 15 minutes, until pastry is set and pale golden. Remove foil and weights and bake shell an additional 5-10 minutes, until pale golden all over. Transfer tart pan to rack.
Next make the filling. Reduce oven temperature to 350 F.
Whisk together eggs, brown sugar, corn syrup, butter, salt and vanilla in a bowl until smooth, then mix in cranberries and walnuts.
Pour filling into shell and bake until filling is set and golden, about 40-45 minutes. If the edges of the tart start to darken before filling is set, cover edges with foil. Place tart on wire rack and cool completely.
The tart can made up to a day ahead and kept covered, at room temperature.