NOTE: this makes TWO galette crusts! I highly suggest following this recipe and making two - stick one in the freezer so you have it when needed. You can freeze it for 3 months!

Add the flour, pistachios and sugar to a food processor and pulse just until combined. In a small bowl, whisk together the egg, vinegar and water. Add the cold butter pieces into the food processor and pulse until small coarse crumbs remain. Sprinkle the water/egg mixture over the flour and pulse again until the dough comes together.

Remove the dough with your hands and divide it in half. Form each half into a disc and wrap it in plastic wrap. This dough makes enough for 2 galette crusts! One can go right in the freezer to save.

Refrigerate the dough for 30 minutes. Freeze one of the other balls of dough!

After 30 minutes, preheat the oven to 400 degrees F.

Place the blueberries in a large bowl. Stir together the sugar, cornstarch , lemon juice and salt. Pour it over the fruit and toss well.

Remove the crust from the fridge. Roll the crust into a “rustic” shape – like a big circle with ragged edges, until it is about 1/4 inch thick. Place the dough on a parchment-lined baking sheet.

Layer the berries in the center leaving a 2-inch+ border of crust. Once the fruit is layered, fold the crust over top of it. Brush the crust with the beaten egg wash.

Sprinkle some chopped pistachios on top. You can also add on some coarse sugar if you wish!

Bake the galette until the crust is golden and the fruit is syrupy, about 40 to 45 minutes.The blueberries may burst a bit. Let it cool slightly before serving with ice cream and chopped pistachios.