1double pie cruststore-bought like *Bake House Creations Pie Crust from ALDI or homemade
Remove the two pie disks from the fridge and set on the kitchen counter.
In a large mixing bowl, add the blueberries, blackberries, raspberries, brown sugar, white sugar, vanilla bean, corn starch, lemon zest, lemon juice and salt. Set aside.
Roll out the first pie crust to fit your 9-inch pie pan. (If you need help, check out my Pie Crust 101 post)
Toss the filling together, and then pour the filling into the pie crust; set aside. I made a tightly woven lattice top, but you definitely don’t have to do this. For something quick and easy, roll out the second pie disk, lay it on top of the filling and trim the pie crust all the way around, leaving a 1/2-inch. Fold over the edges and crimp the pie dough all the way around. Cut a few slits in the top! Or, you could stamp out shapes using a cookie cutter like hearts, stars, etc. and place them on top of the filling.
Or, you can do as I did, which is create a lattice! To do so, cut the rolled out pie dough into 1/2-inch wide to 1/4-inch wide strips. Lay the strips side by side, and weave them under and over each other, creating a lattice. You’ll definitely have to re-roll the scraps to create more strips. I re-rolled the scraps, cut strips and braided them to create a braided edge. I couldn’t do one big continuous braid so it ended up being three braided pieces. Trim the pie crust all the way around, leaving 1/4-inch. Tuck the edges of the pie crust over and gently press it down. Brush the edge of the pie crust with egg wash and place the braided pieces on top. Attach the braided pieces by brushing them with egg wash and pressing them together. This will ensure they’re bound to one another. Transfer the pie to the freezer to chill for 30 minutes.
Preheat the oven to 400 degrees F. Brush the pie with the egg wash and sprinkle with demerara (totally optional!). Transfer to the oven to bake for 20 to 25 minutes. If at any time the pie crust edge gets too brown, you can place a few strips of foil over it to create a tent. Turn the oven down to 300 degrees F and bake for an additional 30 minutes.