As so many people are salivating over it, here's the recipe:
500g potatoes, peeled and cut into chunks
sea salt and freshly ground black pepper
500g asparagus spears, woody ends removed
200g filo pastry
100g butter, melted
100g freshy grated Lancashire cheese
100g freshly grated cheddar cheese
3 large organic or free range eggs
285ml double cream
1/2 a nutmeg
Boil potatoes in salted water for 15 minutes.
Blanch asparagus in boiling water for 4 minutes - drain.
Preheat oven to 190C.
Place a layer of filo pastry into a rectangular baking dish (Jamie used one with a removable base) - it looked about the size of a lamington tin to me (perhaps with slightly higher sides). Let the filo hang about 1" over the sides.
Brush with melted butter and lay another piece of filo over. Repeat until you have 5 sheets of filo in the dish.
Cover with a damp tea-towel while you do the filling.
Drain the potatoes and put them into a big bowl along with the cheeses and mash, using a potato masher.
Mix together the eggs and the cream, then stir that into the mashed potato.
Grate in the nutmeg - (or you could just sprinkle in some ground nutmeg) - and season well with salt and pepper.
Spoon the potato into the pastry case then scrunch up the overhanging bits of pastry to make a rim.
Now lay the asparagus lengthwise along the tart, making sure the top is all covered. (Jamie placed the asaparagus spears about 1/4" apart - one with the tip at one end, and the next with the tip at the other end).
Brush all over with remaining melted butter and bake on the bottom shelf of the oven for about 20 minutes or until crisp and golden.
Rest for 10 - 20 minutes before serving.
Serve with a salad.