Preheat oven to  325°F.  Mix the flour, baking powder, and salt together in a large bowl. Add the butter and use your fingers to pinch the butter and the flour mixture together, gently. You want little pea sized pieces of butter speckled throughout the dough as that’s what make scones fluffy.  When it’s all combined, it will resemble large bread crumbs.

Use a wooden spoon to mix in the brown sugar and blueberries, and then add the buttermilk. If the dough is sticky, add more flour, 1 tablespoon at a time, until the dough has the texture of clay. If it’s too dry, add more buttermilk, 1 tablespoon at a time, until it’s wet enough.

Turn the dough out onto a floured work surface and roll it out into a rectangle 1/4 inch thick. Cut the dough into 3-inch circles trying not to touch or work the dough too much. Leftover scraps can be rerolled to make more scones.

Oil a baking sheet and lay the scones on the sheet. Bake the scones until the tops are golden brown, about 30 minutes. Freeze up to a month.