Hazelnut Espresso Caramel Tart

Hazelnut Espresso Caramel Tart

Ingredients

Tart Dough :

• 11⁄4 cups all-purpose flour
• 1⁄4 teaspoon fine sea salt
• 1 cup (2 sticks) unsalted butter, cut into 1⁄ 2-inch pieces, chilled
• 4 tablespoons ice water, as needed
• 1⁄ 8 teaspoon cider vinegar
• 11⁄ 2 cups (6 ounces) hazelnuts

Espresso-Caramel Syrup :

• 1⁄ 2 cup granulated sugar
• 1⁄4 cup hot freshly brewed espresso, or 1 tablespoon instant espresso dissolved in 1⁄4 cup boiling water

Hazelnut Pastry Cream :

• 2 tablespoons whole milk
• 2 tablespoons cornstarch
• 2 cups heavy cream
• 1 large egg plus 1 large egg yolk
• 1⁄ 3 cup plus 1 tablespoon granulated sugar
• Zest of 1⁄4 lemon, removed with a vegetable peeler, cut into strips
• 4 tablespoons (1⁄ 2 stick) unsalted butter, cut into 1⁄ 2-inch pieces
• 1 teaspoon vanilla extract

Bittersweet Chocolate Glaze :

• 5 ounces bittersweet chocolate, chopped coarsely
• 6 tablespoons unsalted butter, cut into 1⁄ 2-inch pieces
• 1 tablespoon light corn syrup

Cooking Instructions: 

Art Dough: 

1.  Whisk the flour and salt together in a medium size bowl. 
2. Add the butter. Using a pastry blender, cut in the butter until the mixture resembles coarse crumbs. 
3. Mix together the ice water and vinegar. Using a fork, stir enough of the ice water mixture into the flour mixture for the dough to begin to come together into a ball. If the dough is too dry, add more ice water, 1 teaspoon at a time. Do not overmix.
4. Shape into a thick disk and wrap in plastic wrap. Refrigerate until chilled, at least 1 hour and up to 2 hours. 
5. Unwrap the dough and place on a lightly floured work surface. 
6. Roll out the dough into 14-inch round about 1⁄ 8 inch thick. 
7. Transfer the dough to a 9-inch tart pan, being sure that the dough fits snugly in the corners of the pan. 
8. Allow the excess to hang over the edges and fold this under to align with the rim of the pan, creating a double thickness at the sides of the pan. 
9. Press the sides in firmly so the dough edge rises about 1⁄ 8 inch above the edge of the pan, as it will shrink while baking. Line the dough with aluminum foil. Refrigerate for 30 minutes.
10. Position a rack in the lower third of the oven and preheat to 350°F. Top the aluminum foil–covered dough with aluminum pie weights or dried beans. Place the pan on a baking sheet. Bake until the edges of the dough are lightly browned, about 15 minutes. 
11. Remove the baking sheet with the pan from the oven. Remove the foil with the weights. Return the sheet and pan to the oven and bake until the crust is golden brown, 10 to 15 minutes more. Transfer to a wire cake rack and let cool completely.
12. While the oven is still hot, toast the hazelnuts. Spread the hazelnuts on a rimmed baking sheet. Bake in a preheated 350°F oven, stirring occasionally, until the skins are cracked and the nut is lightly toasted, about 10 minutes. 
13. Transfer to a clean kitchen towel and let cool for a few minutes. Rub the nuts in the towel to remove as much of the skin as possible—a few clinging skins won’t hurt. You will use 1⁄2 cup of the hazelnuts in the pastry cream, and the remainder to garnish the tart.

Espresso-Caramel Syrup: 

1. combine the sugar and 2 tablespoons of water in a heavy-bottomed, small saucepan. 
2. Bring to a boil over high heat, stirring constantly until the sugar dissolves. 
3. Stop stirring and boil, occasionally swirling the pan by its handle and brushing down any crystals that form on the sides of the pan with a pastry brush dipped in cold water, until the mixture turns dark caramel brown (you may see a wisp of smoke), about 5 minutes. 
4. Use your nose as well as your eyes here, and detect a sharp, toasted aroma before you deem the caramel finished.
5. Remove the pan from the heat. Carefully—it will bubble up—stir in the espresso until combined. 
6. If the caramel solidifies, return the saucepan to low heat and stir until it dissolves. Pour into a glass measuring cup and let cool completely.

Pastry Cream: 

1.  Pour the milk into a heavy-bottomed medium size saucepan. 
2. Sprinkle in the cornstarch and whisk to dissolve. 
3. Whisk together the cream, egg, egg yolk, and 1⁄3 cup of sugar in a medium-size bowl, then whisk into the milk mixture. 
4. Add the lemon zest and the butter. Cook over medium-low heat, stirring constantly, until the mixture comes to full boil. 
5. Remove from the heat and stir in the vanilla. Strain through a wire sieve into a bowl and discard the lemon zest and press a piece of plastic wrap directly on the surface of the pastry cream. Pierce a few slits in the plastic and let cool.
6. Just before assembling the tart, make the chocolate glaze. Melt the chocolate and butter in the top part of a double boiler over hot, not simmering, water, stirring occasionally. Remove from the heat and stir in the corn syrup.

Assemble the Tart: 

1.  Finish the pastry cream. Pulse 1⁄2 cup of the toasted hazelnuts with 1 tablespoon of sugar in a food processor fitted with the metal chopping blade until very finely chopped but not oily. 
2. Add to the cooled pastry cream. Add 1⁄2 cup of the chocolate glaze and 1⁄4 cup of the espresso-caramel syrup (reserve the remaining caramel for later use) and fold everything together to combine. Do not whisk the cooled pastry cream, or it may thin out.
3.  Immediately spread the pastry cream in the cooled tart shell. Drizzle the remaining chocolate glaze in a free-form, decorative pattern on top. 
4. If you wish, spread the glaze evenly in a very thin layer that reaches the crust.
5. Arrange the remaining hazelnuts around the edge of the tart, placing a few in a jumble in the center. Refrigerate until the glaze sets, at least 1 hour.
6.  Remove from the refrigerator 1 hour before serving. Cut into wedges and serve.