Start with one tablespoon of shortening in your Cast Iron Skillet. Place your skillet in the oven and turn on to 500 degrees. By the time you get the rest put together, you'll be ready to use it.
Mix flour, baking soda, and salt. Add the shortening and cut in. Work it with your pastry cutter or a fork until very small clumps are left. Add the Buttermilk. Mix slightly. Knead a bit but not much. Less is better. Flatten out to 1/2" thick. Cut out bisquits with cutter.
Your pan should now be hot enough. Be very careful and use a hot pad to pull the pan out of the oven. Place the bisquits in the shortening. Quickly turn once and place back in the oven. They'll be ready in 10 minutes.