Preparation Steps

• Line a baking sheet with parchment paper. Preheat the oven to 410°F (210°C). Tip: For extra flakiness, place the stick of butter in the freezer for 10 minutes while you gather ingredients.
• In a large bowl, whisk together the flour, sugar, baking powder, salt, lemon zest, and cardamom.
• Using the large holes of a box grater, grate the cold butter directly into the dry mixture. Toss gently with your fingertips to coat the butter shreds so they’re evenly distributed and no large clumps remain.
• In a measuring cup, whisk the cold heavy cream, egg, and vanilla. Pour over the flour mixture and stir with a fork until shaggy and just moistened. If very dry spots remain, drizzle in 1–2 teaspoons more cream.
• Toss the blueberries with 1 teaspoon flour (to minimize purple streaking), then add them to the bowl and fold gently a few times to disperse without crushing.
• Tip the dough onto a lightly floured sheet of parchment. Pat into a 6×8-inch rectangle about 1 inch thick. Fold the rectangle in thirds like a letter, rotate 90°, and pat into a 7-inch round. Slide the parchment onto the prepared baking sheet and refrigerate for 20 minutes.
• Once chilled, cut the round into 8 wedges. Separate the wedges to leave about 2 inches of space. Brush tops lightly with a little cream (from the cup) for shine.
• Bake for 16–20 minutes, until the edges are golden and the centers feel set when gently pressed. Cool on the pan for 10 minutes, then transfer to a rack.
• For the glaze, whisk powdered sugar with 2 tablespoons lemon juice until smooth and drizzly. Add a few drops more juice if needed. Spoon or drizzle over warm scones and let set for 5 minutes before serving.