Thinly slice the cabbage and chop the green onion.

Prepare a thick batter using flour or pancake mix and water.

Mix the cabbage and green onion into the batter.

Add the canned tuna to the batter and mix well.

Heat oil in a pan over medium heat and scoop the batter to form round shapes.

Cook until the bottom is crispy, then flip and cook the other side.

Spread okonomiyaki or tonkatsu sauce evenly over the cooked pancake.

Drizzle mayonnaise over the pancake.