1 ½ all-purpose flour
2 tablespoons granulated sugar
¼ teaspoon baking powder
¼ teaspoon salt
½ cup cold butter, cut into 1/2-inch pieces
½ cup cold buttermilk
3 ½ cups summer berries (your preference)
1/3 cup granulated sugar
3 tablespoons corn flour
1 tablespoon milk
1 tablespoon coarse sparkling sugar
Step 1: In medium bowl, stir together flour, 2 tablespoons granulated sugar, the baking powder and salt. Cut in butter, using pastry blender or fork, until mixture looks like coarse crumbs. Stir in the buttermilk until your dough comes together. Knead 5 to 10 times or until dough is smooth. Shape dough into flattened round disc; wrap in plastic wrap. Refrigerate this for about 45 minutes or until dough is firm and cold.
Step 2: Meanwhile, heat oven to 220°. In a medium bowl, mix your berries with 1/3 cup of granulated sugar. Now slowly add the corn flour until well coated; set aside.
Step 3: Line a large baking tray with baking paper. Using a floured rolling pin, roll your chilled dough on lightly floured surface to 14-inch circle. Roll up one side of dough onto rolling pin and carefully place dough on cookie sheet. Spread fruit mixture on top of rolled-out dough into the centre, leaving a border of about 2 inches on the edge without any filling on it. Fold the 2-inch edge of dough up over the filling. Pleat the crust as necessary.
Step 4: In small bowl, stir egg and milk until well blended. Brush edge of pastry with egg wash; sprinkle 1 tablespoon sparkling sugar over the pastry. Bake for 35 to 40 minutes, or until the crust is golden brown and juices are bubbling. Remove the galette from the oven and leave it to cool for least 2 hours before serving. Serve and enjoy!