In a bowl, mix flour, water, and eggs until smooth. Fold in cabbage, green onions, tenkasu, and pickled ginger.
Heat vegetable oil in a non-stick skillet over medium heat. Pour half the batter into the pan and shape into a round pancake.
Cook for 4–5 minutes until the bottom is golden, flip carefully, and cook another 4–5 minutes.
Transfer to a plate, drizzle with okonomiyaki sauce and Japanese mayo. Sprinkle with bonito flakes and aonori.
Repeat with the remaining batter to make a second pancake. Serve immediately.
Additional Tips
Okonomiyaki is highly customizable — you can add seafood, pork belly, cheese, or mushrooms. The key is to get a crispy exterior while keeping the inside soft. Serve hot and eat immediately for the best texture. Leftovers can be reheated in a skillet to regain crispiness. You can also experiment with different sauces, but the traditional okonomiyaki sauce and Japanese mayo combo is classic.