Prep. Preheat the oven to 375°F. Line a baking sheet with parchment paper and set aside.
Chill. Add the stick of butter to the freezer.
Combine. In a large bowl, combine the flour and baking powder. Grate the chilled butter and gently mix until it forms coarse crumbs; don’t overmix. It should be crumbly, with butter pieces intact.
Mix. In a separate bowl, whisk together the heavy cream, sugar, egg and vanilla.
Combine. Add the wet ingredients to the flour mixture and begin to combine. Gently fold in the blueberries. Transfer the mixture onto a floured surface.
Shape. Shape the mixture into an 8-inch disk and flatten to a ¾-inch thickness.
Cut. Cut the dough into triangles and spread the scones on the baking sheet.
Bake. Bake for 25–30 minutes, or until the scones are lightly golden on top. Let the scones cool completely.
Glaze. Combine the powdered sugar with lemon juice and drizzle over the top of the scones.