5 cups or 2 1/2 pints fresh blueberries
1 cup sugar
1/4 cup flour
pinch of salt
juice from 1/2 lemon or 1 tbsp lemon juice
2 cups all purpose flour, sifted
3/4 vegetable shortening
4-6 tbsp ice cold water
Rinse the blueberries and set aside. To make the pastry, sift 2 cups all purpose flour into a medium bowl, then add cubes of shortening. Using a pastry cutter, combine flour and shortening together. Add 4 tbsp ice cold water, and continue to blend. Add more water as necessary (1 -2 tbsp) to create the right consistency of dough. It should be slightly sticky and crumbly at the same time. Using your hands, gather dough into a ball, touching as little as possible (dough needs to stay cold). Separate dough into 2/3 and 1/3 discs, wrap in plastic wrap and put in the fridge for 30 minutes, and up to 2 days.
When dough has chilled, take the 2/3 disc and roll out onto a lightly floured surface. Flip into a pie plate and put into the freezer to chill. Add the sugar, flour, and lemon juice to the blueberries and mix gently until blueberries are covered in the sugar/flour mixture. Remove pie crust from freezer and pour blueberries into crust.
Roll out the 1/3 disc of pastry on a lightly floured surface. To make a lattice top, cut the dough into strips using a pizza cutter. Lay 5 strips of dough over the pie - longest in the middle, and shortest on the far sides. Roll back the 2nd and 4th strips, and place a shorter strip perpendicular. Roll the 2nd and 4th strips back over the pie, and roll back the 1st, 3rd, and 5th strips. Place the next horizontal strip on the pie and roll the 1st, 3rd, and 5th strips back, and so on, until the whole pie is covered. This website is a great resource: http://www.simplyrecipes.com/recipes/how_to_make_a_lattice_top_for_a_pie_crust/
Brush the pastry with egg wash before baking for a golden brown crust. Bake at 425 degrees for 30 minutes. Turn oven temperature down to 375 and bake for a further 30 minutes or until pie crust is evenly brown and blueberries are bubbling over the edges. Don't forget to put a cookie sheet underneath to catch the drips!
Cool pie before serving if you want your pie to be less runny, otherwise, slightly cool and serve with a scoop of vanilla ice cream!