1Preheat oven to 375 degrees F. Unroll the pie crusts and press into two 9-inch pie plates. Poke plenty of holes into the surface of the dough with a fork. Bake in preheated oven for 15 minutes, or until lightly browned. Decrease oven temperature to 350 degrees F.
2Heat the olive oil in a skillet over medium heat. Add leeks and cook until soft, 3 to 5 minutes. In a medium bowl, combine the leeks, tomatoes, parsley, mushrooms, salt and pepper. Add the cheese and mix well. Divide the mixture between the two pie plates.
3In another medium bowl, whisk together the eggs and milk. Divide between the two pie plates and pour over the top of the veggie-cheese mixture. Bake in the preheated oven for 50 minutes, or until eggs are cooked through. Let cool for 20 minutes.