Preheat oven to 400°F and lightly grease a baking sheet. Before you begin, pop the butter in the freezer to get extra cold and measure/prep ingredients.
In a large mixing bowl, stir together dry ingredients: flour, sugar, baking powder, baking soda, salt.
Cut in the butter with a pastry cutter. No pastry cutter? Grate very cold butter using a box grater then cut into the flour mixture using a pair of knives.
Next add the zest of one whole lemon.
In a separate bowl, whisk together egg, milk or buttermilk and vanilla. Use a fork to move the flour mixture to the sides of the bowl, making a hole in the middle, then pour egg mixture into the center. Stir until just moistened, then carefully fold in blueberries.
Grab a sheet of parchment paper and lightly sprinkle with flour to prevent sticking. Gently fold your dough (careful not to crusht the blueberries) a few times if possible. Shape dough into an 8-inch circle on a baking sheet lined with parchment paper. Cut dough into 8-10 wedges, cutting into, but not all the way through, the dough.
If you've decided to add the glaze prior to baking, add a light drizzle to the scones and sprinkle each with a teeny bit of turbinado sugar. If you want a visible glaze, simply add after baking!
Bake at 400°F for 15-20 minutes, or until golden and cooked through, using a toothpick to test the center.
Move to a wire rack to cool and enjoy!
Notes
Nutrition Facts below are estimated for scones with glaze and optional sugar topping using an online recipe nutrition calculator. Adjust as needed and enjoy!