01 - Preheat the oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together the flour, sugar, baking powder, baking soda, salt, and lemon zest.
03 - Add the cold, cubed butter to the dry mixture. Cut in with a pastry cutter or fingertips until the texture resembles coarse crumbs.
04 - In a separate bowl, whisk together the heavy cream, egg, vanilla extract, and lemon juice.
05 - Pour the wet ingredients into the dry mix and stir gently just until a shaggy dough forms.
06 - Fold the blueberries into the dough carefully to distribute evenly without crushing.
07 - Turn the dough onto a lightly floured surface. Pat it into a 7-inch round about 1 inch thick.
08 - Cut the round into 8 wedges and place them slightly apart on the prepared baking sheet.
09 - Brush the tops lightly with additional heavy cream.
10 - Bake for 16 to 18 minutes until the scones are golden brown and cooked through. Cool on a wire rack.
11 - Whisk together powdered sugar, lemon juice, and lemon zest until smooth and pourable.
12 - When scones have cooled mostly, drizzle with the lemon glaze and let set before serving.