Special equipment: a 9-inch pie pan a docker or fork pie weights or dry beans cookie cutters
For the crust: In a stand mixer fitted with the paddle attachment, combine the flour, sugar and salt. With the mixer running, drop in the butter and mix until the mixture resembles wet sand. In a small bowl, whisk together the cream and egg yolks, then pour into the mixer and whip until just combined. Turn the dough out onto a clean cutting board and cut in half. Using your hands, gently push each half of dough into a disc and wrap each in plastic wrap. Refrigerate for at least 6 hours or up to overnight.
For the cookie dough: In the bowl of a stand mixer fitted with the paddle attachment, beat the butter with the sugar. Beat in the egg yolks one at a time, then add the vanilla and salt. Add the flour, a little at a time, until incorporated. Divide the dough into small batches and color each with food coloring, as desired. Chill the dough for 1 hour before rolling. When ready to decorate the pie, roll the dough to 1/4-inch thick. Use cookie cutters or a knife to cut out shapes for decorating the pie. For the filling: In a large mixing bowl, whisk the sugar, eggs and yolks until the mixture turns a light, golden color. Then whisk in the buttermilk, cornmeal, flour, cinnamon, vanilla and salt. While whisking, slowly drizzle in the browned butter.
For the pie: Preheat the oven to 400 degrees F. Spray a 9-inch pie pan with cooking spray. Gently dust a clean work surface with flour, then place a pie dough disk on top and use a rolling pin to roll out the dough into a large circle, about 1/4-inch thick. Transfer the dough to the pie pan, then crimp the edges and prick the dough on the bottom with a docker or fork. Line the crust with parchment paper and fill with pie weights or dried beans to weigh the dough down. Bake until the dough just sets, 8 minutes. Remove the crust from the oven and reduce the oven temperature to 350 degrees F. Working quickly, use a pastry brush to brush the crust with egg wash. Carefully pour the filling into the crust.
Bake the pie until set but slightly jiggly, about 35 minutes, covering the edges of the crust with foil to prevent burning after about 10 minutes. Add the cookie dough topper decorations to the pie, then bake for 10 minutes more. Check the pie at about 40 minutes total; the center should still have a jiggle to it, but it should seem mostly set. Cool completely before decorating the pie with dragees, glitter and icing.
This recipe makes enough pie dough for two pies; save the second half of the pie dough for another use.