Makes one 10-inch pie, serves 12

Over the years, we've made more than 8,000 of these pies at Frontera, each crust rolled out by hand by Gonzalo de Santiago, our pastry chef of nine years, and his crew. I put together the recipe a dozen years ago, because I love pecan pie and thought that stirring in chunks of chocolate could make this favorite from both sides of the border seem less cloying. It does, though the result is still rich -- almost like a not-too-sweet candy bar packed into a flaky crust. Barely sweetened whipped cream (laced with a little kahlua) plays the welcome role of counterbalance.

Ingredients:

For the crust:
1 1/2 (6 3/4 ounces) all-purpose flour (measured by scooping and leveling)
6 tablespoons (3 ounces) chilled unsalted butter, cut into 1/2 inch bits
3 tablespoons vegetable shortening or rich-tasting lard, chilled and cut into 1/2 inch bits
3/4 teaspoon sugar
1/4 teaspoon salt
1 egg yolk, beaten slightly

For the filling:
2 cups (about 6 ounces) pecan halves (make sure they're fresh and richly flavorful)
6 ounces semisweet or bittersweet chocolate
3 tablespoons all-purpose flour
3/4 cup (6 ounces) room-temperature unsalted butter
1 cup firmly packed dark brown sugar
5 large eggs, room temperature
3/4 cup light corn syrup
1/4 cup molasses
1 1/2 tablespoons kahlua or brandy
2 1/4 teaspoons pure vanilla extract
1/2 teaspoon salt
2 cups Sweetened Whipped Cream (see below) flavored with kahlua for serving

Method:

1. The dough. Measure the flour, butter and shortening (or lard) into a bowl or a food processor fitted with the metal blade. Quickly work the fats into the flour with a pasty blender or pulse the food processor until the flour looks a little damp (not powdery) but tiny bits of fat are still visible. If using the food processor, transfer the mixture to a bowl.

Mix together the sugar, salt and 3 tablespoons and ice water. Using a fork, little by little work the ice-water mixture into the flour mixture. The dough will be in rough, rather stiff clumps; if there is unincorporated flour in the bottom of the bowl, sprinkle in a little more ice water and use the fork to work it together. Press the dough together into a flat disk, wrap in plastic and refrigerate at least 1 hour.

On a lightly floured surface, roll the dough into a 12 inch circle. Transfer to a deep 10 inch glass pan (I find it easiest to roll the dough onto a rolling pin, then unroll it onto the pie pan). Decoratively crimp the edge and trim excess dough. Refrigerate 30 minutes.

2. Prebaking the crust. Heat the oven to 400 degrees. Lightly oil a 15 inch piece of foil and lay it, oiled side down, into the crust (heavy duty foil is too stiff to work here); press down to line the crust snugly. Fill with beans or pie weights and bake about 15 minutes, until beginning to brown around the edges. Reduce the oven temperature to 350 degrees. Carefully remove the beans or weights and foil, return the crust to the oven and bake 8 to 10 minutes, until it no longer looks moist. (If it bubbles at this point, gently press it down with the back of a spoon.) Brush the beaten egg yolk over the crust, then let it cool completely.

3. The nuts and the chocolate. While the crust is cooling, spread the pecans on a baking sheet and toast in the 350 degree oven until fragrant, about 10 minutes. Cool, then break into small pieces and transfer to a large bowl. Chop the chocolate into rough, 1/2 inch pieces and add to the bowl, along with the flour. Stir until everything is well coated.

4. The filling. In a food processor (or in the large bowl of an electric mixer), cream the butter and brown sugar until light and fluffy, about 3 minutes in the processor, 5 minutes in the mixer. With the machine still running, add the eggs one at a time, letting each be completely incorporated before adding the next. Beat in the corn syrup, molasses, Kahlua or brandy, vanilla and salt.

5. Baking. Pour the filling over the chocolate and pecans and stir well to combine. Pour the mixture into the prebaked pie shell, set onto the lower shelf of the oven and bake until a knife inserted into the center in withdrawn clean, about 1 hour.

Cool completely on a wire rack. Serve slices of the pie at room temperature or slightly warm, topped with a dollop of Kahlua-spiked, sweetened whipped cream.

Advance preparation:

The pie can be made several days ahead, wrapped in plastic and refrigerated. It freezes well. Because the pie is easiest to cut when cold, I suggest making it ahead, refrigerating it, cutting it, then warming just before serving.

Variations and improvements:

Other nuts can be substituted for the pecans. Honey can replace the molasses for a lighter flavor. If you like the crystalline crunch of Mexican chocolate, reduce the semisweet chocolate to 5 ounces and sprinkle the pie with 1/3 cup rather finely chopped Mexican chocolate before baking.

Two 9-inch pies:

Prepare 1 1/2 times the dough, divide it and roll out each half to line 2 shallow 9-inch pie pans; crimp and refrigerate. Divide the filling between the crusts and bake at 325 degrees for 45 to 50 minutes.

To dollop on or over a dessert:
Beat the cream at a moderate speed, or by hand, until it holds lucious soft peaks, then whip in a little powdered sugar and vanilla or liqueurs.

To use as a filling or frosting:
Place everything in your mixer bowl (granulated sugar works fine here since it's going in from the beginning), turn the mixer on medium-high and beat until very stiff - a couple of steps away from butter, stiff enough to pipe easily into a firm shape, but not so stiff that liquid is beginning to weep out. For a cup of cream, sugar can vary from I tablespoon to 4, vanilla 1 to 2 teaspoons, and liqueur about double that. A cup of cream will yield nearly 2 cups whipped.