Gather all ingredients. Set an oven rack to the lowest position and preheat the oven to 375 degrees F (190 degrees C). Mix sugar, cornstarch, cinnamon, and salt together in a bowl; sprinkle over blueberries. Line a pie dish with one pie crust. Pour berry mixture into the crust and dot with butter. Cut remaining pastry into 1/2- to 3/4-inch-wide strips. Use the strips to weave a lattice top. Crimp and flute the edges. Bake pie on the lowest oven rack until filling is bubbling and crust is golden brown, about 50 minutes. Cut into slices and enjoy! Yields one pie.