Add 4 inches of oil to a deep fryer or dutch open. Preheat oil to 350°F.
Place the cut hot dogs and cornstarch into a gallon-sized ziptop bag. Close the bag and shake to coat the hot dogs in the cornstarch.
Insert a skewer into each hot dog piece and place them on a sheet pan. Repeat with the remaining hot dogs.
In a medium-sized bowl, whisk to combine the cornmeal, flour, sugar, baking powder, garlic powder, onion powder, salt, and pepper. Set aside.
In another bowl whisk together the milk, melted butter, and egg.
Add the wet ingredients to the dry and whisk together until there are no lumps. Let the batter sit for 5 minutes. Meanwhile, set up your frying station with a paper towel-lined plate and sheet pan topped with a wire rack.
Pour the batter into a cup. Grab a skewered hot dog by the stick and dip it into the batter until it is fully coated. Let any excess drip off and immediately lower it slowly into the hot oil. I only work with two corn dogs at a time.
Fry until golden brown on all sides, and flip the corn dogs around so they are evenly browned for about 5 minutes.
Place the corn dogs briefly on a paper-towel-lined plate to absorb any excess oil. Then immediately transfer them to a wire rack over a sheet tray to catch any drips. Repeat with the remaining hot dogs and batter.
Serve on their own or with your favorite dipping sauce.
Notes
Add some chopped-up jalapeno or corn kernels to the batter for a fun twist. Refrigerate leftover corn dogs for up to 3 days.