In a mixing bowl, combine the sliced strawberries, granulated sugar, fresh lemon juice, cornstarch, and finely chopped basil. Toss gently until well coated and let sit for 10 minutes.
On a lightly floured surface, roll out your pie crust into a circle approximately 12 inches in diameter and transfer to a parchment-lined baking sheet.
Spoon the strawberry mixture into the center of the dough, leaving a 2-inch border around the edges.
Gently fold the edges of the dough over the filling, creating pleats for a rustic look.
Apply the beaten egg to the edges of the dough with a pastry brush.
Sprinkle the coarse sugar over the crust.
Bake in the preheated oven for 25-30 minutes, or until the crust is golden brown and the filling is bubbling.
Allow the galette to cool for 10 minutes before slicing.
Notes
Serve warm or at room temperature. Garnish with fresh basil and vanilla ice cream for an indulgent treat.