Preheat oven to 425 degrees. Place prepared pie crust in a 9" pie dish. Poke the bottom with a fork or the tip of a sharp knife help it cook thoroughly and flute edges, if desired.
In a small bowl, combine the mascarpone cheese, 1/4 cup granulated sugar, egg, and the vanilla. Beat with an electric mixer on low to medium speed until smooth. Place bowl in refrigerator to chill while preparing pumpkin layer.
In a medium bowl, combine the pumpkin puree, half and half, 1/4 cup granulated sugar, the brown sugar, 2 eggs, and Frangelico. Stir with a wooden spoon till well combined. Add cinnamon, ginger, salt, and nutmeg.
Pour mascarpone cheese mixture into crust, spreading evenly. Slowly pour pumpkin mixture over mascarpone cheese mixture. Use a knife to swirl together into a pretty pattern.
Bake for 15 minutes at 425 degrees. Reduce oven temperature to 350 degrees and bake for a additional 40 to 50 minutes, or until a knife inserted near the center comes out clean.
Cool pie on a wire rack. Cover and chill within 2 hours.
Serve with lots of whipped cream!
Inspired by BHG.com