How to Make It
Heat oil in a large Dutch oven to 350°F over medium heat. Meanwhile, insert skewers into franks, so that at least 2 inches are still exposed on one end.
Whisk together cornmeal, flour, sugar, cornstarch, baking powder, salt, buttermilk, and egg in a medium bowl until smooth. Transfer batter to a tall quart-sized glass.
Dip hotdogs, 1 at a time, in batter. Immediately place dipped hotdogs in hot oil. Fry in batches of 2 until golden and crisp, about 2 minutes, turning constantly to help with even browning. Transfer to a wire rack set over a baking sheet to drip excess oil while you continue with remaining batter and hotdogs.