Warm Chocolate Tart

To make the chocolate decorations: Chill a marble slab or similar smooth surface in the refrigerator.

Work with cool hands in a cool room. Shave one-fourth of the chocolate and set aside. Melt the remaining chocolate in the top of a double boiler over barely simmering water and heat to 110 F. Do not allow any water to come in contact with the chocolate. Remove from heat and set the chocolate pan on a towel to hold it in place. Slowly stir in the shaved chocolate, cooling the chocolate to 90 F. Keep the chocolate in the 90 – 95 F range as you work.

Put the marble on a work surface; wipe before spreading out the chocolate to be sure there is no condensation on it. Spoon or pour about 2 tablespoons of chocolate on the marble. With a thin metal spatula, immediately spread the chocolate into a very thin 6-inch circle. When the chocolate has cooled enough to lose its wet gloss, lift the edges with the spatula, then lift the chocolate and quickly fold the edges under slightly to form a triangular shape. Set on a plate or baking sheet lined with waxed paper, foil, or parchment. Put in the refrigerator to set. Repeat to make 5 or 6 triangular shapes. Store them in a very cool place, or the refrigerator, until ready to use.

To prepare the dough: Combine the sugar, flour, and salt in the bowl of a food processor and pulse a few times to combine. Add the butter in 2 additions, pulsing just until blended. Pulse in the egg. Turn the dough out and form into a flattened ball; wrap in plastic wrap and chill for 30 minutes.

Preheat the oven to 375 F. Grease a bottomless pastry ring and place it on a baking sheet lined with a silicone liner or parchment paper. Roll the dough out into a 1/4-inch-thick circle on a lightly floured surface. Roll the dough up around the rolling pin, transfer to the ring, and unroll it over the ring. Fit the pastry into the ring without stretching it. Press the dough into the bottom edge with your thumb. Pinch the top edge between your forefinger and thumb to create a smooth, slightly thicker edge. Roll the rolling pin across the top to cut off any excess. Prick the bottom of the pastry shell. Bake 12 to 15 minutes, until golden and crisp. Remove and let cool. Reduce the oven heat to 225 F.

To prepare the filling: Put the chocolate in a heat-proof bowl. Combine the cream and milk in a medium saucepan and bring just to a boil. Split the vanilla beans and scrape the seeds into the mixture, then drop in the pods. Take the pan off the heat and pour over the chocolate. Let stand 30 seconds, then slowly stir together with a spatula, working from the center outwards in a spiral. Remove the vanilla bean pod. Stir in the egg(s). Pour the chocolate filling into the tart shell and place in the oven for 5 to 6 minutes. It will be soft in the middle.

To serve: Slip the tart onto a piece of decorative cardboard or a flat plate. Position chocolate triangles on the top, edges down, overlapping each other slightly. Dust with confectioners’ sugar and cocoa. Note that the tart may be served hot, warm, or cold. If you serve it hot, the chocolate garnishes will immediately begin to melt slightly into the top of the tart.