I wonder how many people have received second degree burns from eating hotteok. These chewy, flat buns - sold on the street in Korea - have a wrapper made of wheat flour, glutinous rice flour, yeast and water, and a sweet filling made of peanuts or sesame seeds (and often ground cinnamon) mixed with sugar that turns molten hot when cooked on an oiled griddle. The vendor will slip the hotteok into a paper bag or between a fold of sturdy paper before handing it to the customer, who needs to proceed very carefully: if you bite into it too soon, you'll burn yourself; but if you leave it to cool too much, it becomes leaden.
With hotteok, the proportion of filling to dough needs to be just right, and although some people might disagree, it is possible to have too much filling, which makes the pancake too sweet. If you search the shelves of the Korean markets on Kimberley Street, you'll find boxes of hotteok mixes but it's just for the wrapper - you still need to make the filling, then shape and cook the pancakes yourself. And you're paying a lot for convenience; as with any other dough, the one for hotteok isn't difficult to make. Filling and shaping them is another matter, because if the dough is stretched too thin, the filling will ooze out and make a caramelised, burnt mess on the griddle.