A Swiss Nut tart from Johnny Iuzinni and his book Sugar Rush.
196 g cold unsalted butter
198 g almond paste
219 g flour
1 teaspoon salt
200 g sugar
2 tablespoons water
1 1/2 tablespoons light corn syrup
1 teaspoon kosher salt
225 g heavy cream
366 g chopped walnuts and pecans mixed
1 large egg
1 teaspoon milk
For tart dough, put the butter, almond paste into a standing mixer bowl fitted with the paddle and beat on medium speed for about 5 minutes until the butter and almond paste are combined with no butter clumps visible. With the mixer on low speed, slowly add the flour and salt and mix, stopping to scrape down eh bowl with a spatula occasionally, until the dough is smooth. Divide the dough into 2 equal portions, form each into a disk, and wrap each tightly in plastic wrap. Refrigerate for at least an hour.
On a lightly floured work surface, roll one of the dough disks into an 11-inch circle and carefully press it into a 8-inch removable-bottom fluted tart pan allowing the excess dough to hang over the edges of the pan. Roll the other portion of dough into a 10-inch circle and transfer it to a lightly floured baking sheet. Chill the two crusts int he refrigerator while you make the filling.
For the filling, put the sugar, water, corn syrup, and salt into a heavy saucepan and stir with your finger until mixture is sandy. Wipe the edges of the pan with a wet finger and put the pan over medium-high heat and bring to a boil. Once the sugar is dissolved, brush the edges of the pan with a clean pastry brush dipped in cold water. Cook, without stirring, for about 5 minutes, until the sugar turns a deep mahogany brown and beginning to smoke.
Meanwhile, warm the cream in another saucepan over medium heat until warm. When the caramel is ready, slowly and carefully whisk in the warm cream. Bring the mixture back to a boil and stir in the nuts. Remove from the heat and pour the filling into a large bowl to cool.
Preheat oven to 375 degrees. F.
To assemble the tart, pour the cooled filling into the bottom shell and spread evenly. Carefully lay the pastry circle on top of the filling and press on it lightly to compact the filling and seat it at the edges. Lightly press the bottom and top crust together at the edges, trimming away any excess dough.
Whisk the egg and milk in a small bowl and brush the top. Place the tart on a baking sheet and bake for 35-50 minutes until crust is deep golden brown. Cool the tart completely in pan before slicing. Keep covered and at room temperature.