Preheat oven to 400°F (200°C).

Mix flour, sugar, and baking powder in a large bowl until well combined.

Add cold butter and use a pastry blender or fingers to work it into the dry ingredients until the mixture resembles coarse crumbs.

Stir in lemon zest and blueberries.

Whisk together heavy cream, egg, and lemon juice in a separate bowl.

Pour the wet ingredients into the dry ingredients and stir until the dough comes together in a shaggy mass.

Turn the dough out onto a floured surface and knead it a few times until it comes together.

Pat the dough into a circle that is about 1 inch (2.5 cm) thick.

Cut the dough into wedges or use a biscuit cutter to create scones.

Place the scones on a baking sheet lined with parchment paper, leaving about 1 inch (2.5 cm) of space between each scone.

Brush the tops of the scones with a little extra heavy cream