Heat oven to 375℉/190℃.
Line a sheet pan with parchment paper. Set aside.
Whisk buttermilk and egg together in a small bowl. Set aside.
In a large bowl, sift flour, sugar, baking powder, and salt together.
Grate butter into flour mixture.
Toss gently to coat.
Add buttermilk mixture.
Mix well.
Turn out onto a lightly floured surface.
Sprinkle top with flour.
Roll dough into a rectangle about ½ inch thick.
Use a sharp cutter 3 inch cutter to cut out shortcakes, re-rolling scraps as necessary.
Bake for 20-25 minutes, or until golden brown.