Kimchi jeon is what Korean cooks make when the jar at the back of the fridge has gone properly sour. That extra fermentation is not a problem to be hidden - it is the whole point, giving the pancake a tang that a fresh batch of kimchi simply cannot.
The batter is barely a batter: plain flour, a good measure of rice flour for crispness, ice-cold water and the kimchi juice itself, which stains everything a deep orange-red. Keep it thin. A thick pancake steams rather than fries and you lose the lacy, crisp edges that make it worth eating.
Fry it in more oil than feels reasonable, press it flat, and flip only once. Cut into wedges with kitchen scissors, Korean style, and eat straight from the pan with the soy dipping sauce.
