Preheat oven to 400°F (200°C). Set a rack in the lower-middle position so the bottom crust browns evenly.

Roll one pie crust into a 9-inch pie plate. Press gently into the corners and trim any overhang if needed.

In a large bowl, gently combine fresh raspberries, granulated sugar, cornstarch, lemon juice, vanilla extract, and salt. Mix just until the raspberries are coated and the cornstarch looks evenly distributed.

Pour the filling into the prepared crust. Spread it out evenly so the bake sets up uniformly.

Place the second pie crust over the filling or create a lattice top. Trim and crimp the edges to seal and prevent leaks.

Whisk together large egg and water. Brush the crust with the egg wash for a glossy golden finish.

Sprinkle coarse sugar for topping over the crust. Cut vents if using a full top crust so steam can escape.

Bake for 20 minutes at 400°F (200°C). Look for the crust to start turning golden at the edges while the filling begins to warm.

Reduce oven temperature to 375°F (190°C) and continue baking for 30–35 minutes. Bake until the filling is bubbling through the vents and the crust is a deep golden brown.

Cool completely before slicing to allow the filling to set. Wait until the pie is firm enough that the filling holds shape when cut.