• Preheat your oven to a toasty 400°F (200°C). Line a sheet pan with parchment paper.
• In the bowl of an electric mixer fitted with the paddle attachment, mix 4 cups (500g) of flour, ¼ cup (50g) of granulated sugar, the baking powder, salt, and lemon zest.
• Add in the cold butter and set the mixer to its lowest speed until the butter is the size of peas.
• In a separate bowl, whisk together the eggs and heavy cream. With the mixer on low speed, slowly add this mixture to the flour and butter mixture. Mix until just blended. Your dough might look a bit lumpy, and that's just fine
• Toss the blueberries with 1 tablespoon (8g) of flour to prevent sinking. Gently fold them into the dough by hand to avoid crushing them.
• Transfer your dough onto a generously floured surface and knead it into a ball. Make sure your hands and rolling pin have a dusting of flour to prevent sticking.
• Keep it moving on the floured surface so it doesn't get clingy.
• For Round Scones: Flour a 3-inch (7.5 cm) round plain or fluted cutter and cut circles of dough. Place the scones on the prepared sheet pan. Collect the scraps, roll them out again, and cut more circles.

  For Triangle Scones: Alternatively, shape the dough into two squares and slice each square into quarters. Take each quarter and cut it diagonally, creating charming little triangles.
• Brush the tops of the scones with the egg wash, sprinkle with granulated sugar, and bake for 20 to 25 minutes, until the tops are golden brown and the insides are fully baked. The scones should be firm to the touch.
• Allow the scones to cool for 15 minutes.

For the lemon glaze:

• Meanwhile, whisk together the confectioners’ sugar and lemon juice until smooth. Drizzle the glaze over the scones.