Sweet Potato Pie With Marshmallow Whip

Directions

Pie Crust

1. Whisk 1⅔ cups (208 g) all-purpose flour, 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt, and ¼ tsp. baking powder in a large bowl. Add 2 oz. (56 g) chilled cream cheese, cut into 1" pieces, and rub into dry ingredients with your fingers until fully incorporated (mixture will look very shaggy). Add 10 Tbsp. (140 g) chilled unsalted butter, sliced ½" thick, and toss to coat in flour, then smash into smaller, flatter pieces (about chickpea-size).
2. Make a well in the center and pour in ¼ cup (60 g) ice water. Toss mixture with a fork or your hands to distribute, then knead in bowl a couple times to bring dough together (some dry bits may remain).
3. Turn out dough onto a surface lightly dusted with rice flour or all-purpose flour; dust top of dough with flour. Roll out to a ½"-thick rectangle. Fold dough in half, rotate 90°, and fold in half again. Roll out again to a ½"-thick rectangle and repeat folding process, dusting with more flour as needed to prevent sticking. Pat into a ½"-thick disk and wrap tightly in plastic. Chill in refrigerator at least 2 hours and, preferably, up to 12 hours.
4. Place a rack in middle of oven; preheat to 425°. Remove dough from refrigerator and let sit at room temperature 5 minutes. Unwrap and roll out on a lightly floured surface to about a 12" round about ⅛" thick. Brush excess flour off dough and transfer to a 9"-diameter pie pan. Lift edges and allow dough to slump down into pan, then press dough firmly into bottom and sides. Trim, leaving about 1" overhang. Fold overhang onto itself, pressing firmly to seal; crimp edges if desired. Prick bottom all over with a fork. Chill 15 minutes.
5. Line crust (including crimped edges) with foil and fill with pie weights or dried beans. Bake until edges start to brown, 15–20 minutes. Lift out foil and weights and brush bottom of crust with 1 large egg white (this will create a barrier between crust and filling that prevents crust from getting soggy). Reduce oven temperature to 325° and bake crust until bottom is pale golden brown, 5–10 minutes. Let cool; keep oven on.

Filling and Assembly

1. While the crust is baking, place 1½ lb. sweet potatoes (about 2 large or 3 medium), peeled, cut into 2" pieces, and one 2" piece ginger, peeled, lightly smashed, in a medium pot and pour in water to cover by 2". Bring to a boil, then reduce heat and simmer until sweet potatoes are tender enough to easily pierce with a fork, 14–16 minutes. Drain and let cool slightly.
2. Transfer sweet potatoes and ginger to a food processor and process until mostly smooth. Add 3 large eggs, ½ cup heavy cream, ½ cup granulated sugar, ½ cup (packed) light brown sugar, 2 tsp. Diamond Crystal or 1¼ Morton kosher salt, 1½ tsp. ground cinnamon, 1½ tsp. vanilla extract, ¼ tsp. ground cardamom, and ¼ tsp. ground nutmeg and process until combined and filling is very smooth.
3. Pour filling into crust and smooth top. Bake pie until filling is just set but still jiggles slightly in the center, 50–60 minutes. Transfer to a wire rack and let cool.
4. Meanwhile, using an electric mixer on medium-high speed, beat remaining 1 cup heavy cream in a medium bowl until stiff peaks form, about 3 minutes. Reduce speed to low and add one 7.5-oz. jar marshmallow creme and remaining ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt; beat until combined.
5. Cut pie into wedges and serve with whipped cream.