Geometric Pie - Master recipes

Ingredients

• 3 c. all-purpose flour -
• 1/2 tsp. kosher salt -
• 2 1/2 sticks (10 oz) unsalted butter), cut into ¼ inch pieces -
• 6 tbsp.  ice water, plus more if needed -
• 2 lb. fruit (such as apples, peaches or berries) skinned, pitted and cored -
• 1 c. sugar -
• 1/3 c. cornstarch -
• 1 tsp. vanilla extract -
• 1/4 tsp. ground cinnamon -
• Zest and juice of one lemon -
• 1 large egg  -
• 1/2 tsp. kosher salt  -