Make the Crust:

1. Preheat oven to 350℉.
2. In a food processor, pulse gingersnap crumbs, butter, brown sugar, and salt until moistened. Press into a deep 9-inch pie dish.
3. Bake 12–13 minutes until crisp and slightly darker. Press back edges if needed. Let cool.

Make the Filling:

1. In a saucepan, combine cranberries, 1 cup sugar, and 1/4 cup water. Bring to boil, simmer 15–20 minutes until thick.
2. Puree cranberry mixture until smooth. Add eggs, egg yolks, zest, juice, salt, and remaining sugar to the food processor and pulse to combine.
3. Pour mixture into a heatproof bowl over simmering water. Stir constantly until thickened to 165℉, about 15–20 minutes.
4. Strain through a fine mesh strainer to remove skins. Let cool until barely warm.
5. Beat in softened butter, one piece at a time, until incorporated and lighter in color, about 6 minutes.
6. Pour curd into crust, smooth top, and chill at least 8 hours or overnight.
7. Top with sugared cranberries and serve with whipped cream.