Sweet Potato Pie Vlf

Preheat oven to 425. Lightly spray 2 pie pans with nonstick cooking spray. Cook the sweet potatoes until very soft. Mash very well. Combine sugar, spices in a little bowl. Last add vanilla with the spices and then mix into the potatoes. Beat egg whites and mix it in with the potato mixture. Slowly mix in evaporated skim milk and set aside. Take out the entire stack of phyllo sheets from the box. Turn pie pans over and cut the entire stack to the approximate circumference of the pan so you'll have a stack of circular dough. Quickly, (dough dries out very fast and sticks together) layer 1 or 2 sheets of phyllo on each of the pans, spraying very lightly with non-stick cooking spray. Sprinkle with sugar. Repeat until crust is the thickness you desire. Moisten fingers to seal the edge of the crust and crimp as with a regular crust. Cover edges of crust loosely with foil. Pour filling into the phyllo crust. Sprinkle chopped chestnuts and cinnamon on top if desired. Bake for 15 minutes at 425. Reduce temperature to 350 and bake for about 30 minutes more.