For the crust, whisk the flour, sugar, and salt together in a medium bowl. Using a pastry cutter or fork, cut in the butter until the mixture resembles coarse pea-sized crumbs. Add the water and stir until the flour is moistened. If dough seems dry, add 1–2 more tablespoons of water. Turn the dough out onto a lightly floured work surface and, using your hands, work the dough into a ball. Flatten into a thick disc. Wrap the dough disc in plastic wrap and refrigerate for at least 1 hour.

While the dough chills, prepare the filling. Mix the apples, brown sugar, lemon juice, cornstarch, cinnamon, ginger, salt, and vanilla together in a large bowl. Cover tightly and let sit in the refrigerator until the dough is ready. Line a large baking sheet with parchment paper.

On a lightly floured surface, roll the dough into a 12-inch circle. Transfer the dough to the prepared baking sheet. Arrange the apples in the center of the dough, leaving a 2- to 3-inch border all around them. You can spoon the filling on or arrange the apple slices in a more deliberate overlapping design. Gently fold the edges of the dough over the filling, overlapping the dough as necessary. Press gently to seal the edges. Brush the crust with the egg wash and sprinkle the crust with raw sugar. Dot apples in center with small cubes of butter. Refrigerate shaped galette for at least 15–20 minutes.

Preheat oven to 400 degrees F. Bake until the filling is bubbly and the crust is golden brown, about 40 minutes. Remove from the oven.

Warm up apricot jam or jelly in a small pot on stovetop and brush over exposed apple slices to glaze. Allow galette to cool on the baking sheet for 10 minutes before slicing and serving. Serve with vanilla ice cream or whipped cream, if desired.