Spinach, Pancetta, And Roasted Garlic Tart

P?E BRIS?: In the bowl of a food processor, add flour, salt, and sugar.
All ingredients should be cold. Add the pieces of butter, and process for
approximately 10 seconds or until the mixture resemble a coarse meal. (To
mix by hand, combine the dry ingredients in a large mixing bowl. Using a
pastry blender or two table knives, cut in the butter until the mixture
resembles coarse meal.) Add 1/4 to 1/2 cup ice water, drop by drop, through
the feed tube with the machine running, just until the dough holds together
without being wet or sticky; do not process more than 30 seconds. Test the
dough at this point by squeezing a small amount together. If it is crumbly,
add a bit more water. Turn the dough out onto a large piece of plastic
wrap. Grasping the ends of the plastic wrap with your hands, press the
dough into a flat circle with your fists. This makes rolling easier than if
the pastry is chilled as a ball. Wrap the dough in the plastic, and chill
for at least an hour. (Makes two 8- to 10-inch tarts) TART: Heat oven to
350 degrees. Place garlic in ovenproof dish, and bake until soft, 40 to 45
minutes. When cool enough to handle, cut 1/2-inch off the top and squeeze
out pulp. Set aside. On a lightly floured surface, roll out pastry to a
thickness of 1/8-inch. Place pastry in an 11-inch tart pan; press to fit
into bottom and up the sides of pan. Trim excess pastry by rolling the
rolling pin across the top. Refrigerate for 1 hour. Heat oven to 375
degrees. Line pastry with parchment paper, pressing into the edges, and
fill with pie weights, beans, or rice. Place on baking sheet, and bake for
20 to 25 minutes. Heat 2 tablespoons water in a large saut?pan over medium
heat. Add spinach, cover and cook until spinach is barely wilted, 2 to 3
minutes. Remove with tongs to a colander, and set aside to cool. When
spinach is cool enough to handle, squeeze out excess water. Chop coarsely
and set aside. Heat olive oil in a large saut?pan over medium heat. Add
pancetta, and cook until pancetta has rendered much of its fat. Add onions,
and cook until softened, 7 to 10 minutes. Uncover, raise heat to high.
Stirring constantly, cook until mixture turns a rich golden brown, 3 to 5
minutes. Stir in the spinach and roasted garlic. Season with salt and
pepper. Turn the filling into a bowl, and cool. Blend in the cheese and
eggs. Pour filling into prepared tart shell. Bake until the filling is set
and the pastry browned, about 45 minutes. Cut into 8 wedges, and serve hot.
Serves 6 to 8.