Roll out pie crust to ½" thickness and lay on top of parchment paper-lined baking sheet.
In a large bowl, gently mix blueberries, sugar, lemon zest, lemon juice, vanilla extract, and flour.
Pour blueberry mixture into the center of the thawed pie crust and fold in edges to create a crust. The crust should be 2 to 3" wide. It's okay if some of the edges overlap.
In a small bowl, whisk together egg yolk and water. Brush the folded edges with egg wash and then sprinkle with turbinado sugar.
Bake for approximately 40 minutes or until golden brown.
Serve with whipped cream or vanilla ice cream.
Recipe by Chef Times Two at https://www.cheftimestwo.com/rustic-blueberry-crostata/