Lemon Mascarpone Brûlée Tarts

Attention:  To all of you lemon lovers out there... this may be the best lemon tart you will ever make!  Yes, I know... a very bold statement for me to make, especially after swooning over the lemon meringue tart I recently made for my daughter's birthday.  But this lemon tart is perfect.  A very rich, tart lemon curd is folded into whipped mascarpone and heavy cream and this combo is used to fill the prebaked pecan tart pastry.  A sheer coating of extra-fine sugar is then torched, resulting in a thick, creamy, lemon brûlée.  Served with raspberry sauce and fresh berries, this is one knock-out dessert.  This recipe makes 8 individual tarts, but could easily be prepared in a 9 or 10-inch tart pan.

                  Lemon Mascarpone Brûlée Tarts with Raspberry Sauce
        adapted from a recipe by pastry chef Stacey Cosor, printed in Gourmet

For Tart Shell:
• 1 1/2 sticks (3/4 cup) cold, unsalted butter
• 2 cups all-purpose flour
• 3/4 cup pecans
• 3 tablespoons granulated sugar
• 1/2 teaspoon salt
• 1/4 cup milk
For Filling:
• 1 stick (1/2 cup) unsalted butter
• 1 1/2 cups granulated sugar
• 1/3 cup fresh lemon juice
• 3 whole large eggs
• 3 large egg yolks
• 2 tablespoons freshly grated lemon zest (from about 1 1/2 lemons)
• 3/4 cup mascarpone cheese
• 6 tablespoons heavy cream
For Sauce:
• 1 1/2 cups fresh or thawed frozen raspberries (not in syrup)
• 2 tablespoons granulated sugar
• 1 tablespoon fresh lemon juice

• 1/2 cup superfine granulated sugar (I pulse sugar in a processor for several seconds)

Make shells:
  Cut butter into 1/2-inch pieces.  In a food processor combine flour, pecans, sugar, and salt and pulse until finely ground.  Add butter and pulse until mixture resembles coarse meal.  Add milk and pulse until a dough just forms.  Form dough into a flattened disk and chill, wrapped in plastic wrap, at least 1 hour and up to 1 day.
  Press dough (about 1/3 cup for each shell) onto bottoms and up sides of eight 4 1/2-inch fluted tart pans with removable rims.  Prick bottoms of shells all over with a fork.  Freeze shells 1 hour.
  Preheat oven to 350˚F.  Line shells with foil and fill with dried rice or beans.
  Arrange shells in a shallow baking pan and bake in middle of oven 18 minutes.  Remove foil and rice and continue to bake until golden.  Cool shells in pans on a rack.  Shells may be made 1 day ahead and kept, covered, at room temperature.
Make filling:
  In a heavy saucepan combine butter, 3/4 cup sugar, and lemon juice over moderately high heat, stirring occasionally until butter is melted.  Bring mixture to a boil, stirring, and remove pan from heat.  In a bowl whisk together whole eggs, yolks, and remaining 3/4 cup sugar until thick and pale.  Add hot butter mixture in a stream, whisking constantly, and transfer to pan.  Cook mixture over moderate heat, stirring constantly, until thick and just beginning to boil.  Pour mixture through a fine sieve into a heatproof bowl and stir in zest.  Cool lemon mixture completely, its surface covered with buttered wax paper, and chill at least 8 hours and up to 1 day.
  In another bowl with an electric mixer beat together mascarpone and cream until thick and smooth.  Fold in 1 1/2 cups lemon mixture, reserving remainder for another use, until combined well.
  Divide filling among shells, smoothing tops.  Chill tarts, loosely covered, at least 1 hour and up to 1 day.
Make sauce:
  In a blender purée sauce ingredients and pour through a fine sieve into a bowl, pressing on solids.

  Sprinkle about 1 tablespoon superfine sugar evenly over each tart and caramelize with a blowtorch, moving flame evenly back and forth over sugar (not the crust) until melted and caramelized, about 30 seconds.  (Alternatively, caramelize sugar under a preheated broiler.  If using broiler, cover crusts with pieces of foil to prevent burning).
  Serve tarts with raspberry sauce.  Makes 8 individual tarts.