In a medium-size bowl whisk together the buttermilk, baking powder, baking soda, egg, hot sauce, 3/4 teaspoon salt, 1/8 teaspoon pepper, and garlic powder.
Place the 2 cups of flour in a shallow dish. (A pie baking dish seems to work fine for this)
Roll the steak in the flour, then the batter, and then in the flour mixture again pressing firmly to coat – set aside.
Heat the oil in a cast iron skillet to 325F. Cook the steaks on both sides until golden brown, or to the desired doneness. About 5 minutes on each side.
For well done an instant-read thermometer should read 155F. Remove the steaks to a serving platter covered with paper toweling to drain any excess oil.
When the steaks are done reserve 1/4 cup of the oil and discard the rest. Using the same skillet with the reserved oil whisk in a 1/4 cup of flour until smooth, stir in the regular milk, salt, and pepper to taste and cook over medium heat until thickened.