Preheat oven to 350°F

Butter a baking sheet

Whisk the bread flour, cake flour, baking, baking powder, sugar and salt in a large bowl.

Work in the shorting with your. fingers until the mixture is combined.

Beat the eggs and buttermilk, then stir into the flour mixture with a fork to make a shaggy dough.

Turn out the dough out onto a lightly flouered surface and roll put to 1/4 inch thick.

Cut out biscuits using a 2 1/2 inch round cutter or glass, rerolling the scraps as needed. Tranfer to the prepared baking sheet.

Brush with the beaten egg.

Bake until golden brown and puffy, 18 to 20 minutes.

Tranfer to a rack and let cool slightly. Serve warm