caramelized onion tart

preheat the oven to 400 degs f make up some pastry dough using: 1 stick butter 2 cups of flour 1 large pinch of salt 5 tablespoons cold water mix together the flour, salt and butter until it resembles rough breadcrumbs. add water tablespoon by tablespoon until the dough holds together when you "squeeze' it. it shouldn't be sticky. i used 4 tablespoons this time. now form it into a ball and flatten into a disc shape, about 2 inches in height. wrap it up in serran wrap and refrigerate for 30 mins. in the meantime, make your filling using: 5 small onions (i used yellow ones) 2 whole anchovies (i used salted ones, rinsed them well with cold water, removed the spine and then sliced them diagonally) herbs de provence 4 eggs 1/2 teaspoon grated nutmeg black pepper salt 1 cup of cream 4 tablespoons butter slice the onions and cook on a low heat in 4 tablespoons of butter for 20 mins or until they are soft and translucent. add the sliced anchovies, a large pinch of salt, black pepper and a teaspoon of herbs de provence. mix well. whisk the nutmeg, eggs and cream together and add to the onion mixture. remove your dough from the fridge and roll out enough to line an 11inch pastry tin, with 1/2 inch hangover. bake this blind at 400 degs f for 20 mins using ceramic beads and tin foil to weight the pastry case down. if you don't have ceramic beads, use raw rice grains. after baking blind, remove the beads and foil, and pour in the onion mixture. spread the onions out evenly and now bake again for 25 mins. the tart is cooked with the top is brown and firm (but be careful not to overcook it). my tart came out looking fab and puffy but after a few minutes the filling deflated slightly. be warned, this happens, i've been told this is normal. phew.