To begin, prepare and refrigerate your pie crust for at least an hour.
Preheat your oven to 425°(F). Place a baking sheet in the oven to heat while the oven gets ready.
In a mixing bowl, combine the heavy whipping cream, sugar, flour, and vanilla. Whisk until blended together. Pour the mixture into your pie crust.
Dot with the butter and then sprinkle the nutmeg over the top.
Bake it on the baking sheet for 10 minutes at 425°(F).
Reduce the heat to 350°(F) and continue to bake for another 55 minutes, or until the crust is golden and the filling is bubbly.
While it bakes, monitor the pie crust. If it begins to get brown too quickly, cover the edges with foil or a pie shield. I covered mine at the 10 minute mark when I reduced the heat.