To Prep
In a large bowl, mix mirin and water, then add the flour. Mix with a whisk until well combined.
To Cook
Heat up a frying pan over medium heat. With a ladle, pour in a little less than ½ of batter into the pan. Spread immediately from the center outwards in circular motion to about 20-23cm in diameter.
Sprinkle in bonito powder liberally and add half of the cabbage. Then add ½ of spring onions and bean shoots on top.
Place 3 slices of pork belly, without overlapping, over the vegetables.
Pour 1-2 tbsp of batter over the ingredients to bind them together.
Flip the okonomiyaki carefully to cook the meat with medium high heat until done, then reduce the heat to low.
Heat oil in another frying pan and stir-fry 1 packet of noodles with 1½ tbsp of okonomiyaki sauce, while shaping them to the size of the okonomiyaki. Transfer the okonomiyaki on top of the noodles with 2 spatulas.
In the empty frying pan, heat some oil and add 1 egg. Spread the egg immediately into a circle of the size of the okonomiyaki. Transfer the okonomiyaki, with noodle at the bottom, onto the egg.
Fry the egg until cooked and check that it is not sticking to the pan. Transfer the okonomiyaki to a serving plate by placing the plate on top of the okonomiyaki and flip over.
Add okonomiyaki sauce, mayonnaise and seaweed powder on top. Repeat to make the second okonomiyaki. Serve hot.