1Line a rimmed baking sheet with parchment paper. Pat the hot dogs very dry with paper towels, then push a skewer into one end of each, about two-thirds of the way through.
2Stir the corn muffin mix, egg, milk and 2 tablespoons flour together in a bowl until just combined. The batter should be thick, so add another spoonful of flour if it seems loose.
3Scrape the batter into a tall glass, filling it nearly to the top. Roll each hot dog in a little flour and tap off the extra.
4Dunk each hot dog straight down into the glass, twist as you lift it out, let the extra drip off, and lay it on the parchment-lined sheet.
5Freeze the sheet for 15 minutes to set the batter. While it chills, heat the air fryer to 370°F.
6Spray the basket well with cooking spray, then arrange the corn dogs in a single layer with a little space between them, in two batches if needed. Lightly spray the tops.
7Air fry for 6 minutes, carefully turn each one over, and cook 4 to 6 minutes more, until deep golden and set through.
8Rest for 2 minutes, since the centers are very hot, and serve with ketchup and mustard.