Mix flour, salt, and sugar.

Add the butter and mix it until the mixture looks like bread crumbs

Add water one table spoon at a time and mix until the dough forms a ball

Roll it out between two pieces of plastic wraps and let it sit in the fridge for at least 1 hour

Mix the blueberries, sugar, flour and corn starch, set aside.

Take the dough out of the fridge, peel off the plastic wraps and transfer it into a baking sheet lined with parchment paper.

Pile the filling in the middle of the dough, leave 1.5 inches at the edge.

Fold the edge over the blueberries.

Cook for 50-55 minutes until the crust is golden brown and the filling is bubbly

Let it cool for 20-30 minutes and then serve.