Whisk flour, sugar, lemon zest, baking powder, and salt together in a large bowl. Grate the frozen butter using a box grater. Add it to the flour mixture and combine with a pastry cutter, two forks, or your fingers until the mixture comes together in pea-sized crumbs. See video above for a closer look at the texture. Place in the refrigerator or freezer as you mix the wet ingredients together.

Whisk ½ cup heavy cream, the egg, and vanilla extract together in a small bowl. Drizzle over the flour mixture, add the blueberries, then mix together until everything appears moistened.

Pour onto the counter and, with floured hands, work dough into a ball as best you can. Dough will be sticky. If it’s too sticky, add a little more flour. If it seems too dry, add 1-2 more Tablespoons heavy cream. Press into an 8-inch disc and, with a sharp knife or bench scraper, cut into 8 wedges.

Brush scones with remaining heavy cream and for extra crunch, sprinkle with coarse sugar. (You can do this before or after refrigerating in the next step.)

Place scones on a plate or lined baking sheet (if your fridge has space!) and refrigerate for at least 15 minutes.

Meanwhile, preheat oven to 400°F (204°C).

Line a large baking sheet with parchment paper or silicone baking mat. After refrigerating, arrange scones 2-3 inches apart on the prepared baking sheet(s).

Bake for 22-25 minutes or until golden brown around the edges and lightly browned on top. Remove from the oven and cool for a few minutes before topping with lemon icing.

Whisk the icing ingredients together. Drizzle over warm scones.

Leftover iced or un-iced scones keep well at room temperature for 2 days or in the refrigerator for 5 days.