How to Make It
In a food processor, combine the flour, cornmeal, salt and sugar. Add the butter and pulse until the mixture resembles coarse meal with some pea-size pieces. With the machine on, drizzle in the ice water and pulse until the dough just comes together. Turn the dough out onto a lightly floured work surface. Gather up any crumbs and knead a few times until the dough holds together. Pat into a 1-inch-thick disk, wrap in plastic and chill until firm, 1 hour.
On a lightly floured work surface, roll out the dough to a 12-inch round, a scant 1/4 inch thick. Ease the dough into a 9-inch glass pie plate. Trim the overhanging dough to 1 inch, fold it under itself and crimp the edge decoratively. Freeze the crust until firm, 30 minutes.
Preheat the oven to 425°. Line the crust with parchment paper and fill with pie weights or dried beans. Bake for 20 minutes, until the side is lightly golden and just set. Remove the paper and pie weights. Cover the crust rim with strips of foil and bake for 15 minutes, until lightly browned on the bottom. Let cool on a rack. Reduce the oven temperature to 375°.
In a small saucepan, melt the butter. Add the vanilla bean and seeds and cook over moderately low heat until the butter is golden brown, about 5 minutes. Remove from the heat and let cool; discard the vanilla bean.
In a medium bowl, using a handheld electric mixer, beat the eggs and egg yolks with the sugar until thick and fluffy, about 3 minutes. Beat in the browned butter, lemon zest, nutmeg and salt, then beat in the flour just until blended.
Spread the raspberries in the crust and pour the custard over the berries. Bake the pie for about 1 hour and 15 minutes, until the filling is set around the edge but slightly jiggly in the center. Transfer to a rack and let cool for 3 hours. Serve with whipped cream.