Begin by preheating your oven to 400°F (200°C) and lining a baking sheet with parchment paper to prevent sticking.
In a large mixing bowl, thoroughly whisk together the all-purpose flour, granulated sugar, baking powder, baking soda, and salt, ensuring everything is evenly distributed.
Next, use a pastry cutter, or your fingers, to incorporate the cold, cubed butter into the dry mixture. Cut until you achieve a texture similar to coarse crumbs, with some larger bits of butter still visible for flakiness.
Carefully fold in the fresh blueberries and freshly grated lemon zest, taking care not to crush the delicate berries as you combine the ingredients.
In a separate small bowl, whisk together the heavy cream, egg, and vanilla extract until well blended.
Gently pour the wet mixture into the dry ingredients and stir until just combined, ensuring you do not overmix—the dough should remain slightly sticky for the best texture.
Transfer the dough onto a lightly floured surface. With clean hands, knead it gently a few times until it holds together. Shape the dough into a circle about 1 inch thick.
Use a sharp knife or a bench scraper to cut the dough into 8 equal wedges, and carefully place them on the prepared baking sheet, spacing them out to allow for expansion during baking.
If you like a little extra sweetness and texture, sprinkle coarse sugar over the tops of each scone.
Bake in the preheated oven for 15-20 minutes, or until the scones are golden brown and a toothpick inserted into the center comes out clean.
Once baked, allow the scones to cool on the baking sheet for a few minutes, then transfer them to a wire rack to cool completely.
Notes
Serve warm with a lemon glaze and fresh blueberries for garnish.