- 1 cup sugar
- Pinch of cream of tartar
- 1 cup heavy cream
- 6 ounces bittersweet to semisweet chocolate (61 to 70 percent cocoa solids)
- 8 tablespoons (4 ounces) butter
- 5 egg yolks
- 1 egg
- ¼ teaspoon salt
- One 9-inch Sweet Tart crust or Hazelnut Crust
- Bain-marie
- 9-inch fluted or straight-sided tart pan
- Prepare and bake the Sweet Tart crust or Hazelnut Crust.
- Make the caramel cream (see the Note on cooking caramel successfully):
- Preheat oven to 325°F. In a medium-sized heavy-bottomed saucepan, combine the sugar, ¼ cup water, and a pinch of cream of tartar or a drop of lemon juice. Cover and bring to a rapid boil over medium-high heat. Boil for 1 minute, uncover, and continue to cook until the sugar caramelizes and becomes a deep, golden brown. Remove the pan from the heat and carefully add the cream (the mixture will bubble and steam furiously). When the bubbling has subsided, return the pan to the heat and whisk the mixture until it comes to a rolling boil. Remove from the heat and let cool for 5 minutes.
- Emulsify the chocolate with the caramel cream and the eggs:
- In the bowl of a bain-marie, combine the chocolate and butter and stir occasionally with a rubber spatula until melted, about 10 minutes. The subtle texture and flavor of this custard rely on keeping the chocolate mixture from becoming too hot. Test the chocolate mixture with your finger as it melts in the bain-marie; if it hurts your finger, the chocolate is too hot. While the chocolate is melting, combine the egg yolks and whole egg in a metal bowl and whisk vigorously until they lighten in color a bit, 1 to 2 minutes. Slowly add the caramel cream to the eggs, whisking constantly until completely incorporated. Slowly add the chocolate mixture to the caramel mixture, whisking continuously. The batter should be shiny and smooth, and hold the lines of the whisk.
- Bake the tart:
- Pour the filling into the prepared tart shell and bake on a cookie tray until the top is shiny and smooth and the center is set, about 30 minutes. To test if the custard is done, gently touch the surface toward the center of the tart. If the custard is still partially liquid and it glazes your finger, bake for an additional 5 minutes. Do not let the filling rise; if it begins to rise, you will end up with a denser tart. Allow the tart to cool for ½ hour on a wire rack before removing it from the metal tart ring.
- Serving Suggestions:
- This tart tastes best served at room temperature or slightly warm. It can be served with a dollop of whipped cream or vanilla ice cream. I also recommend the Espresso Ice Cream or the Cinnamon Caramel Mousse.