Skewer each hot dog half and cheese half together lengthwise onto a stick, leaving a bare handle of skewer at the bottom to hold.

Whisk the flour, sugar, yeast, and salt together. Add the milk and egg and whisk into a thick, smooth batter, roughly the consistency of pancake batter. If using yeast, let it sit in a warm spot for 20 to 30 minutes until slightly puffed; if using baking powder, skip the wait and use it right away.

Pat each skewered stick dry with paper towel — a dry surface is what the batter actually sticks to.

Dip each stick into the batter, turning to coat it in a thick, even layer all the way down.

Immediately roll the battered stick in the drained potato cubes, pressing gently so they stick to the batter on every side.

Heat the oil to 170°C / 340°F. Fry one or two sticks at a time, turning occasionally, for 5 to 6 minutes, until the potato cubes are deep golden and the batter underneath is cooked through.

Drain on a rack for a minute, then roll the hot corn dog in the granulated sugar while it's still warm enough for the sugar to stick.

Serve immediately, with ketchup and mustard drizzled over or on the side.