Directions 14 steps | 135 Minutes
Make the crust. In the bowl of a food processor, pulse together the flour, cornmeal, sugar and salt.
Add the cubed unsalted butter, and pulse until coarse, pea-sized crumbs form.
Add the 4 tablespoons of buttermilk and pulse until evenly moistened. If the mixture seems dry, add up to 2 more tablespoons of buttermilk.
On a sheet of plastic wrap, transfer the flour mixture. Fold the corners of the plastic wrap to form a disc of dough. Wrap and refrigerate for at least 1 hour
While the dough is chilling, prepare the filling. In a large mixing bowl, whisk together the brown sugar, cornstarch, lemon juice and salt.
Peel, core and thinly slice the pears. Add the pears to the bowl and toss until evenly coated. Set aside. (See notes)
Preheat the oven to 400°F. Line a baking sheet with parchment paper or a silicone mat. Remove the pie dough from the refrigerator. On a lightly floured surface, roll the dough out into a 12-inch circle.
Leaving a 2 to 3-inch border from the edge, arrange the pears in a circle on the outer edge of the dough. Add additional rows in a concentric circle.
Fold the edges of the dough, lifting and pressing the edges up and over the fruit. Transfer the galette to the prepared baking sheet and refrigerate for 10 minutes.
Make the egg wash. In a small bowl, whisk together the egg and milk.
Brush the edges of the tart with the egg wash and sprinkle with turbinado sugar. Bake the dough until the filling is tender and the crust is golden brown, about 30-45 minutes. Transfer the galette to a wire rack to cool.
While the galette is cooling, add the preserves into a small saucepan. Heat over low heat until the preserves become liquefied. If the preserves have chunks of fruit in them, strain over a fine-mesh sieve. Use a pastry brush to gently glaze the top of the galette with the preserves.
Let cool for 10-15 minutes before serving with a scoop of vanilla ice cream.
Serve immediately. Enjoy!
Using a mandolin will make it easier to make thin, even slices.