This recipe is one of our desserts to give thanks for.
In a large bowl, gently whisk remaining 1/2 teaspoon salt with rest of ingredients except 1/4 cup sugar, cranberries, and orange juice. The mixture should be smooth and have no bubbles. Place cooled piecrust on a baking sheet; pour in pumpkin filling. Use an offset spatula or the back of a large spoon to smooth the top; transfer to oven. Bake until pumpkin filling is set but still has some wiggle in the center, 60 to 75 minutes. (If edges of pie get too dark toward the end of baking, cover them with aluminum foil.) Cool on a rack.
Meanwhile, set aside a few whole cranberries for garnish (optional). Boil remaining cranberries with 1/4 cup sugar, orange juice, and 1/4 cup water until berries pop, about 3 minutes. Reduce heat and simmer for 3 to 4 minutes. Press berries and cooking liquid through a fine strainer. While sauce is warm (not hot), spread across cooled pie with an offset spatula. Roll reserved berries in sugar (if using) and place on pie. Serve pie at room temperature or cold; it can be refrigerated for up to 1 day.