Pre-cook a pie crust (with holes poked in it) to ¾ done — usually a 450°F oven for 8 minutes. Take crust out and let cool while cooking the filling. Turn the oven down to 350°F.
In the top of double boiler, combine the first 1/3 cup of sugar, salt, spices, and pumpkin. Stir constantly. While stirring, add the egg yolks one at a time. Add sour cream and mix well. Cook over hot (not quite boiling — or at most, not a rolling boil) water until thick, while continuing to stir constantly.
Beat egg whites until they form soft peaks. Gradually beat in the remaining sugar. Fold into the pumpkin mixture.
Turn into three-quarters baked pie shell and bake in 350°F oven for forty-five minutes or until browned and a toothpick comes out clean. Serve with whipped cream, if desired.
Mix flour and salt, add shortening, water, and refrigerate for at least 30 minutes. If you don't know how to make pie crust, you're probably going to want another recipe so that you get all of the steps. This is more for the proportions.