Cake with Custard and Jam (French Gâteaux Basque)

What makes a gâteaux Basque so intriguing is that the cake has a clue as to what's baked inside. If filled with pastry cream, there's a crosshatch pattern on top. If filled with black cherry jam, another regional specialty, there's a Basque cross - a cross shaped like a rounded pinwheel - baked flat on top.

Pastry:
4 oz unsalted butter, at room temperature
½ cup sugar
1 lemon, freshly zested
1/8 tsp. sea salt
1 extra-large egg
1 extra-large egg yolk
1½ cups all-purpose flour, unbleached
1 tsp. baking powder

Filling:
¼ cup + 2 Tbsp. sugar
¼ cup all-purpose flour, unbleached
4 extra-large egg yolks
1¾ cups whole milk
½ vanilla bean, split lengthwise and scraped
1 Tbsp. light rum
½ tsp. pure almond extract
¾ cup black cherry preserves
1 egg, beaten, for egg wash

For the Pastry:
In a bowl of an electric mixer fitted with the paddle attachment, cream the butter, sugar, lemon zest, and salt on low speed, until smooth. Add the egg and egg yolk and mix until blended. In a small bowl, whisk together the flour and baking powder. Add the flour mixture to the butter mixture and mix on low speed until a soft dough forms. Turn the dough out onto a lightly floured work surface and divide it into tow pieces. Wrap in plastic wrap, and refrigerate until firm, at least 30 minutes.

For the Filling:
In a medium bowl, whisk together the sugar and flour. Add the egg yolks and ¼ cup of the milk and whisk until smooth. In a medium saucepan, heat the remaining 1½ cups milk with the vanilla bean and its scrapings, until steaming. While whisking, pour ½ cup of the hot milk into the yolk mixture. Whisk the yolk mixture back into the hot milk and cook over medium heart, whisking, until boiling and thick, about 4 minutes. Strain the filling through a fine mesh sieve into a bowl. Discard the vanilla bean. Stir in the rum and almond extract. Place a piece of plastic wrap directly on the surface of the pastry cream to prevent a skin from forming and refrigerate until cool, at least 2 hours and up to 6 hours.

Preheat the oven to 320°F (160°C, Gas Mark 2). Set a 9" diameter flan ring with 1" sides on a baking sheet lined with parchment paper. Spray the inside of the pan with vegetable oil.

Working between two piece of plastic, roll out the larger disk of dough to an 11" round. Remove the plastic wrap and ease the dough into the flan ring, pressing it into the corners and leaving the overhang. Spread the preserves evenly over the bottom of the pastry shell. Add the pastry cream in dollops and then carefully spread it over the preserves. Working between two more pieces of plastic wrap, roll out the second disk of dough to a 10 inch round and lay it over the pastry cream. Press the edges of the top and bottom crust together and cut off the overhang using the back edge of of a knife. Using the tines of a fork, lightly score the top crust in a crosshatch pattern. Brush the top of the tart with the remaining egg wash. With the tip of a knife, poke 3 holes in the top to allow steam to escape.

Bake in the center of the oven for 55 minutes or until the top is golden brown. Transfer the baking sheet to a wire rack and let the tart cool completely.

Serve at room temperature or chilled, cut into wedges.

Makes 8 servings.