In a large bowl, whisk together the flours, sugar and salt. Scatter the butter pieces over the top and rub with your fingertips until the mixture is the texture of cornmeal with some larger, pea-sized butter chunks remaining. Sprinkle the ice water over 1 tablespoon at a time, tossing with your fingers or a rubber spatula, until the dough begins to clump together and no loose, floury bits remain. Gather the dough into a ball, flatten into a disc and wrap tightly in plastic wrap or a plastic bag. Chill at least 30 minutes, or until firm.
Remove the dough from the fridge and roll out on a lightly floured surface into a 12 - 14" round (depending on the size of your pan). Fit the dough into a 10" or 11" tart pan. Trim the overhang to 1 inch, then fold it over to make a lip, pressing the sides gently.Freeze the tart crust while you prepare the filling ingredients.
For the filling:
Position a rack in the bottom of the oven, place a baking stone on the rack if you've got one, and preheat the oven to 350º.
Place the hazels on a small baking pan and toast 10 - 12 minutes until fragrant and the skins are starting to peel away from the nuts. Let cool until handleable, then rub between your hands to remove as much of the skins as possible. Coarsely chop the nuts.
Increase the oven temperature to 425º.
Measure the crème fraîche and milk in a 2-cup measure, and whisk in the egg, salt and pepper. Arrange the pears in the bottom of the unbaked, frozen tart shell. Crumble the cheese over, and sprinkle with half the nuts. Pour the custard over the pears and sprinkle with the remaining half of the nuts. Immediately place the tart pan on a baking sheet and place in the oven on the baking stone.
Bake the tart until the crust and top are golden, 35 - 40 minutes. Serve warm or at room temperature. The tart is best soon after being baked, but will keep in the fridge for a few days. Warm in the oven or toaster oven before serving.
Notes
This tart can stand many variations. The first time I made it, I used all heavy cream in the custard in place of the crème fraîche and milk. This time around, I used a combination of quark and heavy cream. You can substitute walnuts, pecans, or pine nuts for the hazels if you prefer. If you use apples in place of the pears, slice them 1/8" thick; I would go with fujis, galas or pink ladies. Serve this rich tart with a crisp salad of arugula, beets, fennel and vinaigrette, and a glass of prosecco or sauvignon blanc.All-Butter Pate Brisée can be subsituted with half recipe of sourdough pate brisee. Adapted from Martha Stewart's Baking Handbook.Tart filling adapted from The American Boulangerie.Nutritional values are based on one of eight servings.