8 tablespoons (4 ounces or 113 grams) cold unsalted butter, cut into pieces
1/4 cup ricotta
3-4 tablespoons cold water
2 cups blueberries
3-4 tablespoons granulated sugar (depending on sweetness of berries)
3-4 tablespoons cornstarch
Juice of half a lemon
Pinch of salt
1 egg yolk beaten with 1 teaspoon water
1 heaped teaspoon turbinado or coarse sugar for sprinkling
Directions
Whisk the flour, kosher salt, granulated sugar and zest together in the bottom of a large bowl. Work the butter into the flour with your fingertips or a pastry blender until mixture resembles a coarse meal and the largest bits of butter are the size of tiny peas. Stir ricotta and 3 tablespoons water together in a small dish and pour into butter-flour mixture. Stir together with a flexible spatula as best as you can, then use your hands to knead the mixture into a rough, craggy ball. Wrap in plastic and flatten into a disc. Chill in the fridge for 1 hour or up to 48 hours.
Heat oven to 400 degrees. On a floured counter, roll the dough out into a large round-ish shape, about 14 to 15 inches across.
Transfer dough to a parchment-lined baking sheet by rolling gently onto the floured rolling pin and unrolling onto the baking sheet. Refrigerate for 10 minutes.
Stir the blueberries, 3 to 4 tablespoons granulated sugar, 2 tablespoons cornstarch, lemon juice, and a pinch of salt together. Sprinkle center of chilled dough lightly with flour and sugar - this will protect the dough from getting too wet once the filling is cooked. Spread the filling in the center of the chilled dough, leaving a 2-inch border. Fold the border over the filling, pleating the edge to make it fit.
Whisk egg yolk and water together and brush over exposed crust. Sprinkle with coarse sugar.
Bake galette for 30 minutes, or until golden all over. Remove from the oven and let stand for 5 minutes, then slide the galette onto a serving plate. Cut into wedges or just put a bunch of forks around it and let everyone dig in! Serve hot, warm or at room temperature, preferably with vanilla ice cream.