Pulse flour, sugar and salt in a food processor until combined. Add butter and pulse until the butter pieces are no larger than pea size, about 8-10 pulses.

Stir the ice water and sour cream together in a glass measuring cup. Drizzle over the flour mixture and pulse until moist clumps start to form. Squeeze the dough together in your palm. If it feels dry and won’t hold together, add an additional tablespoon of ice water and pulse again. Repeat as necessary until the dough holds together when squeezed.

Transfer the dough to a piece of plastic wrap and form into a disk. Refrigerate at least an hour and up to 2 days (the dough can also be frozen for up to 1 month. Thaw completely on the counter before continuing with the recipe).

Dust a clean work surface with flour and, using a rolling pin, roll the dough into a 12 inch round. Transfer to a 9 or 10 inch tart pan with a removable bottom (or alternatively a 9 inch pie plate). Press the dough into the tart pan and remove any overhang from the sides of the pan with a sharp knife or pastry scraper (or decoratively crimp the top if using a pie plate). Refrigerate for at least 30 minutes.

Preheat the oven to 375 degrees. Prick the bottom of the tart shell all over with a fork. Cover the tart pan with parchment or foil and fill with pie weights, dried beans or rice. Bake until the crust is dry but still light in color, about 25 minutes. Remove from the oven and take out the foil or parchment along with the weights. Reduce the oven temperature to 350 degrees.

Whisk the eggs, milk, cream, salt and a few grinds of pepper together in a large bowl. Scatter the cheese over the bottom of the warm crust and pour the egg mixture over the top. Transfer to the oven and bake until just set and browned on top, about 25-30 minutes. Cool slightly and serve warm, cut into wedges or squares.