Put dry ingredients in food processor or mixer, add cold butter and pulse until crumbly.
Remove bowl from mixer and add lemon juice and water. Mix by hand with pastry blender until just combined.
Pour out onto a piece of saran wrap and shape into (1) 8" round disk. Refrigerate 10 minutes or overnight.
Place pie disk between 2 pieces of parchment paper and roll out on a pastry mat into round disk 2" larger than your pie plate.
Place dough in pie plate and crimp edges. Pierce pie shell with fork, lightly dust with thickening agent, and brush with egg white wash.
Place a round circle of parchment over the pie and fill bottom with pie weights. Bake pie shell at 400° for 15 minutes.