Heat your oven to 400°F and prepare a baking sheet lined with parchment paper.
Combine flour, sugar, lemon zest, baking powder, baking soda, and salt thoroughly in a large mixing bowl.
Grate cold butter using a box grater with large holes into the flour mixture, then toss until each butter shred is coated evenly.
Gently fold in the fresh blueberries to the mixture.
Stir in the buttermilk and lemon juice with a spatula until the dough begins to form, being careful to keep most blueberries intact.
Avoid overworking the dough; it’s alright to have some floury spots and small crumbles
Lightly flour your countertop then turn out the dough, carefully bringing it together with your hands while not crushing the berries.
Shape the dough into a roughly 15-by-3-inch rectangular slab.
Slice the dough into 10 to 12 triangle pieces using a sharp knife or bench scraper, spacing them about half an inch apart on the sheet.
Brush each scone’s top with melted butter and sprinkle coarse sugar on top.
Bake in the oven for about 15 minutes until the scones turn a very light golden color and feel set in the middle.
Allow scones to cool on the pan or transfer them to a wire rack to reach room temperature.
Whisk together powdered sugar and lemon juice to create a smooth glaze; adjust consistency by adding more lemon juice or powdered sugar as needed.
Drizzle the glaze over the cooled scones for a sweet, tangy finish.
Serve your scones warm or at room temperature for the best taste.
