In a large bowl, combine the cabbage, scallions, panko, and salt. Gently mix in the eggs. (Note: the mixture will be very loose and cabbagey, not like a flour pancake batter. If it's very dry, let it sit for 10 minutes).

Heat a nonstick skillet over medium heat. Brush the skillet with olive oil and use a ¼ measuring cup to scoop the cabbage mixture into the skillet. (It's ok if it doesn't seem cohesive, it'll bind together as the egg cooks). Flatten gently with a spatula so that the mixture is about ½ inch thick. Cook for 3 minutes per side, or until browned, turning the heat to low as needed. Repeat with the remaining mixture, wiping out the skillet and brushing with more oil as needed.

Drizzle the okonomiyaki with Worcestershire sauce and thin strips of squeezed mayo. Top with sesame seeds, pickled ginger, and nori. Sprinkle with microgreens, if desired. Serve hot.