Make the Dough: In a large mixing bowl, combine all-purpose flour, almond flour, sugar, and salt. Add chilled cubed butter and mix with a pastry cutter or your hands until the mixture resembles coarse crumbs.
Add Ice Water: Gradually incorporate ice water, one tablespoon at a time, mixing until the dough begins to form. Avoid overworking the dough. Wrap in plastic wrap and refrigerate for at least 30 minutes.
Prepare Filling: In a separate bowl, toss the sliced pears with lemon juice, brown sugar, cinnamon, and nutmeg. Allow to sit for 15 minutes to let the flavors meld.
Roll Out Dough: Preheat the oven to 400°F (200°C). On a lightly floured surface, roll out the chilled dough into a roughly 12-inch circle. Transfer to a baking sheet lined with parchment paper.
Assemble Galette: Arrange the pear mixture in the center of the rolled-out dough, leaving about 2 inches of border. Fold the edges of the dough over the pears, pleating as you go.
Egg Wash & Almonds: Beat the egg and brush it over the edges of the dough for a golden finish. Sprinkle the sliced almonds over the pears.
Bake: Bake in the preheated oven for 30-35 minutes or until the crust is golden brown and the pears are tender.
Cool & Serve: Allow the galette to cool for about 10 minutes before slicing. Serve warm or at room temperature, optionally with a scoop of vanilla ice cream.
Notes
Serve warm or at room temperature, optionally with vanilla ice cream.