1-Begin by preparing the crust: Whisk together 1 and 1/2 cups all-purpose flour, 2 tablespoons granulated sugar, and 1/4 teaspoon salt in a bowl.

2-Cut in 1/2 cup cold unsalted butter, cubed, until the mixture is crumbly, then add 1/4 cup ice-cold water to form the dough into a disc and chill for at least one hour.

3-For the filling, combine 3 to 4 apples, peeled and sliced into 1/4-inch slices (about 4 to 5 cups), with 1/4 cup packed brown sugar, 1 and 1/2 tablespoons all-purpose flour, 2 teaspoons fresh lemon juice, 1 teaspoon ground cinnamon, and 1/4 teaspoon ground nutmeg.

4-Roll out the chilled dough into a 12-inch circle on a lined baking sheet and arrange the apple filling in the center, leaving a 2 to 3-inch border.

5-Fold the edges of the dough over the filling, brush with the egg wash, and sprinkle with coarse sugar if desired. Optionally, drizzle with salted caramel sauce.

6-Chill the assembled galette for 15 to 20 minutes, then preheat the oven to 400°F (200°C) and bake for about 35 minutes, or until the filling is bubbly and the crust is golden brown. Let it cool for 10 minutes before serving.