Preheat oven to 425 degrees F (220 degrees C).
Place your Buttermilk (1 cup), Butter (2 tablespoon), and Vegetable Shortening (2 tablespoon) the freezer. You want them super chill. Good biscuits are similar to life, they are both only good if everything is as chill as possible throughout the process.
In a large bowl, sift and combine All-Purpose Flour (2 cup), Baking Powder (4 teaspoon), Baking Soda (1/4 teaspoon) and Salt (3/4 teaspoon).
Get handsy with the Butter and Vegetable Shortening. Use your fingertips to rub them into the dry mixture until they are the size of a pea. Toss the bowl into the freezer for 5 to 10 minutes to chill.
Take the Buttermilk out of the freezer along with the mixing bowl of flour and butter. Make a well in the center, and begin to pour in the buttermilk. Stir until it just comes together. Don't over mix!
Turn dough onto a floured surface and dust the top with flour. Gently fold the dough over 5 to 6 times.
Use your hands to press the dough into a 1-inch thick round.
Cut out biscuits using a 2-inch cookie cutter or a glass that's the similar size. Fold over the remaining dough and cut out remaining biscuits. They won't be as pretty, but it's okay.
Beat the Egg (1) to make an egg wash.
Place the biscuits on a baking sheet and brush with a bit of egg wash. Place them so they are just touching. Bake for 15 to 20 minutes until biscuits are nice and golden on top.
Serve with some jam, as the vehicle for a dope breakfast sandwich, and/or drowned in some gravy!