In a large mixing bowl, whisk together all-purpose flour, cornmeal, and salt until combined. Cut in the cold butter until the mixture resembles coarse crumbs. Gradually add ice water, mixing until the dough starts to come together. Form the dough into a ball, wrap in plastic wrap, and refrigerate for 30 minutes.

While the dough chills, wash and slice the strawberries, then place them in a medium bowl. Sprinkle half a cup of sugar over the strawberries and add cornstarch, lemon juice, and lemon zest. Gently toss to coat and let sit for about 10 minutes.

Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Roll out the chilled dough into a rough circle about ¼ inch thick on a lightly floured surface. Transfer the dough to the prepared parchment, then spoon the strawberry mixture into the center, leaving a border of about 2-4 inches. Fold the edges of the dough over the filling.

Brush the exposed edges of the crust with a beaten egg for a golden finish. Sprinkle the remaining tablespoon of sugar over the crust. Bake for 35-40 minutes, or until the crust is golden brown and the filling is bubbling.

Once done, cool on the baking sheet for about 10 minutes. Slice into wedges and serve warm, optionally with vanilla ice cream or whipped cream.