Blueberry Tart with Chocolate Crust

Ingredients

• 1⅓ cups (190 g/6.7 oz) all-purpose flour
• 3 tablespoons (20 g/0.7 oz) unsweetened cocoa powder
• ½ cup (55 g/2 oz) powdered sugar (or ¼ cup granulated sugar)
• Pinch of salt
• 1⅓ sticks (150 g/5.3 oz) cold unsalted butter, cut into small cubes
• 1 large egg
• ½ teaspoon pure vanilla extract, optional
• 1 can blueberry pie filling
• 2 cups Fresh blueberries