In a large mixing bowl, combine gluten-free flour blend and salt, whisking until evenly distributed.

Cut chilled unsalted butter into the flour mixture until the texture resembles coarse crumbs.

In a separate bowl, whisk together egg, lemon juice, and cold water until smooth. Gradually pour into flour and butter blend, stirring gently.

Wrap the dough in plastic wrap and refrigerate for about 15 minutes.

On a lightly floured surface, roll out the chilled dough to about ¼ inch thick.

Carefully lift the rolled-out dough and place it into a greased 9-inch pie pan.

If pre-baking, poke holes in the bottom of the crust and bake at 350°F for 20-25 minutes until lightly golden.

If using a top crust, roll out a second portion of dough and place it over the filling.