1. In food processor, combine flour, sugar, salt, and cinnamon. Pulse to combine. Add cold butter. Pulse until mixture resembles peas. Don’t over mix! You want to see bits of butter, that’s what make the pie dough flaky.
2. Shape dough into a disc and wrap in plastic wrap. Place in the refrigerator and chill for 30 minutes.
3. Meanwhile, toss blueberries with sugar and zest.
4. Preheat oven to 425°F.
5. Remove dough from refrigerator. Roll into a circle on a piece of Gefen Parchment Paper. Transfer parchment and dough to a baking sheet. Add blueberries to the center. Fold dough over the fruit, forming a freeform pie. Brush with egg and sprinkle with sugar.
6. Bake for 30 minutes, or until golden.