Gâteau Basque

In a food processor, pulse the sugar with the butter, lemon zest and salt until smooth. Add the egg and egg yolk and pulse to blend. In a small bowl, whisk the flour with the baking powder. Add the dry ingredients to the processor and pulse until a soft dough forms. Turn the dough out onto a work surface and divide it into 2 pieces, 1 just slightly larger than the other. Pat the dough into disks, wrap in plastic and refrigerate until firm, at least 30 minutes.

In a medium saucepan, heat the milk with the vanilla seeds and bean until steaming. In a medium bowl, whisk the sugar with the egg yolks until pale. Add the flour and whisk until smooth. Gradually add 1/2 cup of the hot milk, whisking vigorously. Pour the mixture back into the saucepan and cook over moderate heat, whisking constantly, until boiling and thick, about 4 minutes. Strain the pastry cream into a bowl through a fine sieve; discard the vanilla bean. Stir in the rum and the almond extract. Cover and refrigerate until chilled and firm.

Preheat the oven to 325°. Butter a 9-by-1-inch flan ring and set it on a cookie sheet lined with parchment paper. Working between 2 pieces of plastic wrap, roll out the larger disk of dough to an 11-inch round. Ease the dough into the flan ring, pressing it into the corners and leaving a slight overhang. Spread the preserves evenly over the bottom of the tart shell. Add the pastry cream in dollops, then carefully spread it over the preserves. Working between 2 more pieces of plastic wrap, roll out the second disk of dough to a 10-inch round and lay it over the pastry cream. Pinch the edges of the top and bottom crusts together and roll the overhang onto the top crust. Using a knife, make shallow slash marks along the edge.

Using the tines of a fork, deeply score the top crust in a crosshatch pattern. Brush with the egg wash. 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.

To unmold, place a second cookie sheet over the tart and invert. Remove the ring and carefully invert the tart onto a cake plate. Cut the tart into wedges and serve.