In a large bowl, rub the lemon zest into the sugar until it feels like damp sand.

Whisk in the flour, baking powder, and salt.

Grate cold butter into the dry ingredients and work it in with your fingers or a pastry cutter until crumbly.

In another bowl, whisk together the egg, heavy cream, lemon juice, and vanilla.

Make a well in the dry mixture, pour in half the wet ingredients, and gently stir. Add the remaining wet mix and fold until just combined.

Gently fold in blueberries.

Turn the dough out onto a lightly floured surface, gently knead into an 8-inch round disk, and freeze for 30–40 minutes.

Preheat oven to 400°F.

Slice the chilled dough into 6–8 wedges and place on a lined baking sheet.

Brush tops with a little cream and bake for 18–22 minutes, until golden.

Cool slightly and drizzle with a simple lemon glaze if desired!