Make pastry as directed in a regular 9-in. pie pan. Let cool.
Meanwhile, preheat oven to 375° and make filling: Bake sweet potatoes in a shallow pan until very tender when pierced, 1 1/4 to 1 3/4 hours. Let cool. Scoop flesh into a food processor and purée until smooth. Measure 2 cups; save extra for soup or another use.
Reduce oven to 350°. With a mixer, beat eggs in a large bowl until frothy. Beat in remaining filling ingredients until blended. Pour into crust and spread level. Wrap pie rim with 4 strips of foil.
Bake pie 30 minutes. Meanwhile, in a small bowl, stir together topping ingredients except pecans until smooth. Stir in pecans.
Remove foil from pie. Evenly drop small spoonfuls of pecan mixture in a border around edge of pie. Continue to bake until center jiggles only slightly when shaken gently, 15 to 20 minutes. Let cool on a rack at least 2 hours.
Make ahead: Through step 2 or the whole pie, up to 1 day.