In a large bowl, combine the cabbage, eggs, and water. Use chopsticks or a whisk to break up the eggs and mix everything together.
*If making the corn, cheese, and mochi version, stir in the corn, the white portions of the green onions, and ½ cup of the mozzarella.
Add the okonomiyaki flour and dashi powder. Stir just until combined.
Heat a large skillet over medium-low heat. Add the neutral oil.
Lay half of the bacon in the pan, then spoon half of the batter directly over the bacon, spreading it into an even round about 1 inch thick.
For the corn version, press half of the cooked mochi onto the top of the pancake and sprinkle with some of the remaining mozzarella.
Cook for 4–5 minutes, until the bacon is crisp and the bottom is golden brown.
Carefully flip and cook another 4–5 minutes until golden and cooked through. Lower the heat if it is browning too quickly.
Repeat with the remaining batter.
Top generously with okonomiyaki sauce, Kewpie mayonnaise, and the reserved green onions.
