Mix the flours then rub in the butter. Add the water and mix to a firm dough. Knead briefly then chill for 30 minutes.
Mix all the vegetables in a roasting tin and add the garlic and rosemary. Sprinkle over some dried mixed herbs if you like. Roast for 35 minutes.
Meanwhile, roll out the pastry and place in a 23cm (9 inch) dish. Cover the pastry with parchment paper and fill the dish with baking beans to hold it down. Bake blind for 15 minutes, then remove the paper and beans and bake for another 5 minutes.
Fill the pastry case with the vegetables and arrange the feta on top. Bake for another 10 minutes then serve.