In a large Dutch oven, pour the vegetable oil to a depth of 4 inches. Heat the oil to 350 degrees F.
Place the cornstarch in a small bowl. Place 1 hot dog piece on the end of each skewer. Dredge the hot dogs in cornstarch, gently tapping off the excess.
In a large bowl, combine the cornmeal mix, flour, and sugar. Add the buttermilk, whisking until smooth.
Holding the ends of the skewers, dip the hot dogs into the cornmeal batter to completely cover the hot dog. Holding the ends of the skewers, carefully place the battered hot dogs into the hot oil. Fry until golden brown, 2 to 3 minutes. Drain on paper towels. Repeat procedure with remaining skewered hotdogs and cornmeal batter.