01 - In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, and fine sea salt. Add cold unsalted butter and work in using a pastry blender or fingertips until the texture resembles coarse crumbs. Add ice water, one tablespoon at a time, mixing gently until the dough just binds together. Shape into a disk, wrap in plastic, and chill for at least 30 minutes.
02 - Cream together almond flour, granulated sugar, and softened butter in a medium bowl until smooth. Incorporate the egg, vanilla extract, almond extract if using, and a pinch of salt, blending until uniform. Reserve at room temperature.
03 - In a separate bowl, gently combine sliced pears with granulated sugar, ground cinnamon, and lemon juice until evenly coated. Set aside.
04 - Preheat the oven to 400°F. On a lightly floured surface, roll out the chilled dough into a 12-inch round. Transfer the rolled dough to a parchment-lined baking sheet.
05 - Spread almond filling evenly over the crust, leaving a 2-inch border. Arrange pear slices in concentric circles atop the almond layer. Fold dough edges inward over the filling, pleating as necessary.
06 - Brush the exposed crust with beaten egg. Sprinkle turbinado sugar on the crust if desired. Bake for 40 to 45 minutes, or until the crust is golden and the pears are tender.
07 - Allow to cool for 15 minutes. Dust with powdered sugar before slicing and serving if preferred.