Preheat the oven to 400 degrees F (200 degrees C).
Whisk together All-Purpose Flour (4 cup), Salt (2 teaspoon), Granulated Sugar (1 tablespoon), and Baking Soda (1 teaspoon).
Make a well in the center of the flour mixture, add the Egg (1), and beat with a fork to incorporate slightly. Add the Buttermilk (1 3/4 cup), followed by the Butter (2 tablespoon) and stir with a rubber spatula until combined. Mixture will be sticky.
Grease a 9 to 10 inch cast iron skillet with butter. Set aside.
Lightly flour your hands and sprinkle a little flour over the sticky dough ball. use your hands to scrape the dough from the sides of the bowl and to quickly shape the mass into a ball, kneading lightly if necessary. Transfer to prepared skillet.
Sprinkle with a teensy bit more flour. Use a sharp knife to make an X across the top of the dough ball. Place in oven and bake for 35-40 minutes or until lightly golden and bottom sounds hollow when tapped.
Remove from oven, transfer to cooling rack, and let cool for 15 minutes before slicing.