Whisk 1½ cups of all-purpose flour, 2 tablespoons of granulated sugar, and ¼ teaspoon of salt. Cut in ½ cup of cold cubed unsalted butter with a pastry cutter until it forms pea-sized crumbs.
Stir in ¼ cup of ice-cold water until the dough comes together, adding a little more if it is dry. Shape into a disc, cover, and refrigerate for at least 1 hour.
Toss 4 cups of peeled, cored, and sliced pears (¼in / 5mm thick) with ¼ cup of granulated sugar, 2 tablespoons of all-purpose flour, 1 teaspoon of lemon juice, ½ teaspoon of ground cinnamon, ¼ teaspoon of ground ginger, and 1 pinch of salt.
Roll the dough into a circle on a floured surface and transfer it to a baking sheet lined with parchment paper. Pile the pears in the center, leaving a wide border, and fold the edges over the fruit.
Refrigerate the galette for 15-20 minutes while you preheat the oven to 400°F / 205°C.
Beat 1 egg with 1 tablespoon of milk and brush it over the crust. Bake for 30-35 minutes, until the crust is golden brown. Cool on the baking sheet for 10 minutes before slicing.
