*To make buttermilk, mix 3/4 cups of milk with 1 tablespoons of lemon juice, and allow to set for 5 minutes.
In a bowl, put the flour, 3 tablespoons of sugar, and lemon zest, and mix. Mix in the cold, grated butter, integrate with a fork. You should have a sandy mixture with some visible pieces of butter.
Add the blueberries, mix, then add the buttermilk and stir with a fork to hydrate all the flour.
Transfer the dough to a slightly floured surface and put together the sandy fragments and flour with your hands, unifying the dough but without kneading it. If the dough is too sticky, put flour on your hands. It is useful to use a spatula to flip the dough or remove it from the surface, and flour the table during this process so that the dough will not stick.
Make a disc and cut it into 8 equal wedges. Cover a baking pan with a baking sheet, sprinkle some flour, and place the scones separate from one another.
Preheat the oven to 400°F.
Put the tray with the scones in the freezer for 10 minutes. Before putting it in the oven, brush the scones with milk and sprinkle 2 tablespoons of brown sugar over them.
Bake for 20 minutes or until the scones are slightly golden. Allow to cool over a baking rack. Serve warm.
