Combine flour, baking powder, salt and sugar in a large bowl. Cut in butter until the mixture has the consistency of coarse meal. Set aside.
In a separate bowl, whisk together 1 egg and the buttermilk and add to the flour and butter mixture. Working quickly, mix just until all the ingredients are moist and the dough comes together. Be careful not to overmix.
Transfer the dough to a smooth, well-floured surface. Roll or pat the dough to a 3/4-inch thickness and cut with a 3-inch cookie or biscuit cutter. Place on baking sheet lined iwth parchment paper so the biscuits are touching eachother. Beat second egg and brush tops of biscuits to glaze.
Bake for 2- minutes or until golden brown. Slide onto rack to cool slightly. Break apart and serve.