Blackberry and Hazelnut Galette

Ingredients

• 4 cup blackberries fresh
• 1 large eggs 
• 1 large egg white 
• 1 tablespoon flour all-purpose plus more for rolling
• 4 teaspoon granulated sugar divided
• 1 cup hazelnuts toasted
• 2 teaspoon juice of lemon fresh
• 1  pie dough (see recipes)
• 1 tablespoon sugar 
• 5 tablespoon butter unsalted at room temperature

Equipment

• food processor
• baking sheet
• oven
• plastic wrap
• stand mixer
• rolling pin

Directions

1. Prepare the Crust (see recipe here http://www.sippitysup.com/perfect-pie-crust): Divide dough in half, shape into 2 discs, one about 5-inches and 1 about 6-inches in diameter, both about 3/4-inch thick. Wrap in plastic. Refrigerate dough at least 1 hour (or up to 2 days), or freeze up to 1 month.Use a lightly floured surface and a lightly floured rolling pin to roll out the larger disc of the chilled dough to about a 12 to 13-inch circle, a generous 1/8-inch thick.
2. Transfer it to a parchment-lined baking sheet then cover lightly with plastic wrap and chill at least 20 minutes or up to overnight. Save smaller disc for another use.Prepare the hazelnut filling: Use a food processor to grind the hazelnuts into a coarse meal.
3. Transfer the ground nuts to a stand mixer.
4. Place oven rack in the center position and heat oven to 400 degrees F.Toss the blackberries with the lemon juice and remaining 2 teaspoons granulated sugar. Set aside about 20 minutes. Meanwhile, remove the plastic from the rolled dough and spread hazelnut filling evenly over the center of the crust leaving about a 2-inch border. Pile the blackberries on op of the hazelnut filling. Fold the exposed edge of dough over filling, pleating as needed to form a neat rounded package. Don’t worry too much about the shape, this is a free form pie. Also don’t try to make the dough meet in the middle. You want to leave the filling exposed.
5. Brush pastry with some egg wash and sprinkle it with turbinado sugar.
6. Bake galette until the crust golden brown and the filling is bubbling, about 55 minutes. Cool galette on rack.
7. Serve warm or at room temperature.