How to Make It
Preheat oven to 350°F with rack in center of oven. Place paper baking cups in a 12-cup muffin pan. Process cookies in a food processor until mixture forms fine crumbs, about 20 seconds. Add melted butter and ¼ teaspoon salt and pulse until combined, 4 to 5 times. Firmly press 1 tablespoon crumb mixture into bottom of each prepared muffin cup. Bake in preheated oven until golden, 10 to 12 minutes. Set aside.
Beat pumpkin, condensed milk, eggs, grated ginger, vanilla, and remaining ¼ teaspoon salt in a large bowl with an electric mixer on medium speed until smooth and well combined. Spoon about ¼ cup pumpkin mixture into each muffin cup. Return to oven, and bake until filling is slightly puffed and set in the center, 22 to 25 minutes. Remove from oven, and let cool in pan 20 minutes. Gently remove pies from muffin pan and transfer to a wire rack. Let cool completely, about 1 hour. Carefully remove paper baking cups from pies.
Beat heavy cream with an electric mixer fitted with a whisk attachment on high speed until soft peaks form, about 3 minutes. Dollop pies with whipped cream, and garnish with crystallized ginger.