• In a large saucepan, add the frozen blueberries, sugar, salt, and vanilla extract. Using a zester, add the zest of the lemon, followed by the juice of the lemon. Turn heat to medium and stir regularly until the blueberry juices start to release.
• Once there is some liquid blueberry juice at the bottom of the saucepan, tip the pot and carefully pour the juice into a small bowl, and stir in the cornstarch. Mix until a uniform pink slurry forms without any cornstarch. Pour this back into the saucepan and stir in with the blueberries. Continue to simmer and stir regularly until the liquid thickens, around 5 minutes. Then remove from heat and allow to cool fully. To speed up cooling, you can pour the blueberry filling into a new bowl.

Prepare the Crust Dough

• Before you begin, make sure your vegan butter is cold. You can even cut it into small cubes and place it in the freezer for a few minutes. Also, ensure your water is ice-cold. Add ice to your water and allow it to cool down for 5-10 minutes before using.
• In a food processor, combine the all-purpose flour, salt, and sugar and pulse to mix.
• Add the cold vegan butter and pulse several times until the mixture resembles coarse crumbs. You should have small pea-sized pieces of fat throughout the dough.
• Gradually add the ice-cold water to the mixture. Add more water, a little at a time, until the dough begins to come together. Be careful not to overwork the dough; it should be just moist enough to hold together.
• Turn the dough out onto a clean, floured surface. Gently knead it a few times until it comes together into a ball. Divide into two even pieces and Flatten into disc shapes. Wrap the each dough patty in plastic wrap and refrigerate it for at least 10-20 minutes. Chilling the dough allows the fats to solidify again, making the crust flaky.
• On a floured surface, roll out one dough patty into a circle slightly larger than your pie dish (about 12 inches in diameter). Roll out from the center, rotating the dough a quarter turn after every few rolls to prevent stretching the dough too much in one direction. Specks of butter in the pie dough are expected and help to make the flaky layers. Carefully lift the rolled-out dough and place it into your pie dish. Gently press it into the bottom and sides of the pan, and leave about 1 inch of dough hanging over the edge (which will be used for crimping later). Place in the refrigerator.

Assemble Your Pie

• Once the blueberry filling has cooled to room temperature fully, preheat the oven to 400 degrees F and add the filling to the crust-lined pie dish.
• Take the second dough patty from the fridge, place on a floured surface, and roll out one dough patty flat just like the first. Using a pastry wheel or knife, slice the dough into lattice strips (approximately 1 inch thick). Place all the strips going one direction over the pie. To create the lattice weave, gently lift and fold alternating strips back while you place the remaining strips laying the opposite direction, and then fold the strips back. Add one new strip at a time until the lattice is complete. Fold the dough hanging over the edge up and over the sides and use your fingers to pinch and crimp the edges to secure an create the classic crimped pie design. Alternately, if you don't have enough dough hanging over the edges, simple use a fork and press it into the edges of the dough to crimp and seal along the entire rim of the pie. Then use a knife or pastry wheel to cut off any dough hanging over the side of the pie dish.
• Brush the pie crust dough lightly with soymilk or agave nectar, and sprinkle with course sugar (if desired), and bake for 40-45 minutes. Check after 30 minutes and if the crust is browning, place a piece of tinfoil over the top.
• Remove to a wire cooling rack and allow to cool fully.