Tart Shell

1 cup all-purpose flour
2 tablespoons granulated sugar
1/4 teaspoon kosher salt
1 stick very cold unsalted butter, diced
2 tablespoons ice water

Place the flour, sugar, and salt in the bowl of a food processor fitted with a steel blade. Pulse a few times to combine.

Add the butter and pulse 12 to 15 times, or until the butter is the size of peas. With the motor running, add the ice water all at once through the feed tube. Keep hitting the pulse button to combine, but stop the machine just before the dough becomes a solid mass.

Turn the dough onto a well-floured board and form into a disk. Wrap with plastic and refrigerate for at least 1 hour. Roll out and line tart pan.

Filling

1/3 cup sugar, scant
4 teaspoons all-purpose flour
2 eggs, beaten
1 cup toasted, peeled, and chopped hazelnuts
2/3 cup bittersweet chocolate chips, chopped
2/3 cup corn syrup, scant
4 teaspoons butter, melted
1/2 teaspoon vanilla extract
1/8 teaspoon salt
1 tart shell, see recipe below or use refrigerated pie dough
Caramel sundae topping
Coarse sea salt

Preheat the oven to 325 degrees. In a large bowl, mix together the sugar and the flour. Add the eggs, hazelnuts, chocolate chips, corn syrup, butter, vanilla, and salt. Stir well. Pour the mixture into the pie crust. Bake for 1 hour.

Cool the tart for at least 30 minutes, drizzle with caramel sauce and sprinkle with sea salt.