It doesn't matter whether the dish is metal or pottery, you should really bake blind to allow the pastry to cook through.
To do this, line the raw pastry with either foil or baking parchment and weigh it down with beans or rice etc. You can buy special blind baking beans, but I'm sure something already in your cupboard will suffice. You can put whatever you use in a jar afterwards and use them time and time again.
My personal favourite quiche is a bacon, mushroom and leek one. I bake the pastry blind and then cover it with a good layer of whole-grain mustard. (More than you think you should use!) Fry bacon, mushrooms and leek and fill the pastry. Then beat up three eggs, 100ml of milk/cream and salt and pepper. Pour into the quiche and cover with grated cheese. Bake at 180 for about 30-40 mins or until set.