Okonomiyaki (Japanese Cabbage Pancake)

Whisk eggs, water, soy sauce and hondashi (if using) in a large bowl. Add flour and baking powder; whisk until smooth. Stir in cabbage and scallions until well combined.

Heat oil in a 10-inch nonstick skillet over medium heat. Add the cabbage mixture and gently spread into an even layer (do not press down). Cover and cook, shaking the pan occasionally, until browned on the bottom, 8 to 10 minutes. Remove the pan from the heat and cover with a rimless plate. Holding the plate tightly against the pan, invert the pan onto the plate so the okonomiyaki transfers to the plate. Slide the okonomiyaki off the plate back into the pan, browned-side up. Return to medium heat; cover and cook, shaking the pan occasionally, until the bottom is browned and the center is set, about 8 minutes.

Meanwhile, whisk mayonnaise and Sriracha in a small bowl.

Transfer the okonomiyaki to a serving plate. Drizzle the Sriracha-mayonnaise mixture over the top in a zigzag pattern. Garnish with sliced scallions and shredded nori, if desired, and slice into 4 pieces.