First you need to cook the pie crust. Pulse all the ingredients for the crust in a food processor, until it starts to form a ball. Turn off the processor and knead the dough with your hands, until a smooth. Wrap it into a plastic food wrap and then put it in the refrigerator for a half an hour. Preheat oven to 375 F. Roll out pastry to 1/8 inch thick (3mm), and line a 9- or 10-inch tart pan. Pierce the crust with a fork for a couple times. Line pastry with parchment paper, fill the paper with a little raw beans or rice, and bake in preheated oven for 15 minutes. Remove parchment and rice, grease the pie with lightly beaten egg. Continue baking another 5 min. Lower the oven heat to 305 F. In a mixing bowl, mix together all the ingredient for filling, but do not over beat. Pour the mixture through a strainer. Place the tart pan on a baking sheet, and carefully pour the lemon mixture into the baked pastry crust. Bake for about 30-40 min until the tart is nearly set. The filling will be runny in the center, and will set when cool. Sprinkle with a confectioners sugar when serve.