Bake sweet potatoes for 1 hour at 350 degrees, or until soft. Cool, peel and puree in the food processor.
Preheat oven to 350 degrees and set a rack in the lowest level. For the bottom crust, lightly flour the work surface and the dough and roll it to a 12-inch disk. Fold the dough in half and place it in the pan; unfold the dough and press it firmly into the pan. Trim away all but 1/2-inch excess dough at edge of pan. Fold dough under and flute edge.
For the filling, scrape pumpkin into a bowl and whisk in eggs and yolks. Whisk in remaining ingredients in order, whisking smooth between each addition. Pour the filling into the prepared pie crust.
Bake the pie for about 1 hour, until the crust is baked through and the filling is set. Cool the pie on a rack.
For Squash Pie, halve, seed and wrap in foil, one large acorn squash and substitute for sweet potatoes, above