In order to make the pancake batter, place the kimchi into a large bowl. Using kitchen shears, cut into small pieces. Then, add the sliced shiitake mushrooms, chopped green onions, jalapeno, and sweetener to your bowl, together with 1 cup of pancake mix.
Slowly pour in your cold water while you stir the batter. When you've added about half the water, stir the batter around to check on its consistency. You do not want too much liquid in your batter. It should be a lot thicker than your breakfast pancake batter. It should be in between regular batter and a paste. Continue adding more water, slowly, until you achieve the right consistency.
To an 8- to 10-inch skillet, add a generous amount of oil over medium-high heat. When the oil shimmers (about one minute), add about 2/3 cup of the batter onto your pan. Using the back of the ladle, spread the batter out so that it is nice and thin, though you don't want any gaps in the batter. Cook the pancake for about 1 minute, until it easily lifts off your pan. If your pancake doesn't easily come off the pan, you can use a spatula to loosen it. Then, lift the pan off the flame and, using a circular motion, swirl your pancake around so that it collects the excess oil. Otherwise the oil will splatter when you flip the pancake.
Flip the pancake (with or without a spatula). Add a little bit more oil around the edges. Cook for another minute until the bottom of the pancake turns a deep, reddish hue. Flip a couple more times until both sides are evenly cooked before placing on a serving plate. Repeat with remaining batter. Garnish and serve immediately.