How to Make It
Prepare the Gingersnap Crust: Preheat oven to 350°F. Combine crumbs and sugar in a small bowl. Add butter; mix well. Press mixture into bottom and sides of a lightly greased 9-inch pie plate. Bake in preheated oven for 10 minutes. Remove and set aside to cool.
Prepare the Filling: In a small bowl, mix together 3 tablespoons whole milk and gelatin; let stand 5 minutes.
In a medium-sized saucepan, whisk together heavy cream, ¾ cup whole milk, sugar, brandy, cinnamon, and nutmeg. Cook over medium-high heat until mixture is steaming and almost boiling (200°F), whisking occasionally.
Remove saucepan from heat and whisk in gelatin mixture (it will be a semisolid gel) until completely dissolved into the hot liquid.
Allow the saucepan to cool at room temperature for 30 minutes, whisking every 10 minutes.
Use a fine wire-mesh strainer to strain the mixture, and pour the strained liquid into prepared Gingersnap Crust. Place in the refrigerator for 5 hours or overnight.
Top the surface with whipped cream and freshly grated nutmeg immediately before serving.