Prep: Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.

Combine Dry Ingredients: In a large bowl, whisk together the flour, granulated sugar, baking powder, and salt.

Cut In Butter: Add the cold, cubed butter. Using a pastry cutter, two forks, or your fingertips, work the butter into the flour mixture until it resembles coarse crumbs with a few pea-sized butter pieces remaining.

Combine Wet Ingredients: In a small bowl or measuring cup, whisk together the cold heavy cream, cold egg, and vanilla extract.

Form Dough: Pour the wet ingredients over the flour-butter mixture. Gently stir with a fork until just combined and a shaggy dough begins to form. Carefully fold in the blueberries, trying not to break them.

Knead & Shape: Turn the dough out onto a lightly floured surface. Gently knead and press the dough together until it just holds its shape (do not overwork it!). Pat the dough into a 7-inch circle, about 1-inch thick.

Cut: Use a sharp knife or bench scraper to cut the circle into 8 equal wedges.

Chill: Place the scones on the prepared baking sheet, at least 2 inches apart. Brush the tops lightly with heavy cream and sprinkle generously with coarse sugar. Place the entire baking sheet in the freezer for 15 minutes to chill.

Bake: Bake for 18-22 minutes, or until the scones are golden brown on top and cooked through. Allow to cool on the baking sheet for 10 minutes before transferring to a wire rack.