Before You Start: If time allows, let the batter rest for at least one hour (and up to overnight) for a fluffier okonomiyaki. Now, gather all the ingredients.
In a large bowl, combine 1 cup all-purpose flour (plain flour), ¼ tsp Diamond Crystal kosher salt, ¼ tsp sugar, and ¼ tsp baking powder. Mix all together.
Peel and grate 5.6 oz nagaimo/yamaimo (mountain yam) in a small bowl. Note: The nagaimo may irritate your skin and cause itchiness. Work quickly and rinse your hands immediately after touching the nagaimo.
Add the grated nagaimo and ¾ cup dashi (Japanese soup stock) to the bowl. Mix it all together until combined and set aside while you prepare the ingredients.
Discard the core of ½ head green cabbage and cut into ½-inch (1.3-cm) slices. Then, mince the cabbage strips. Wash the cabbage and drain well.
Chop ¼ cup pickled red ginger (beni shoga or kizami beni shoga). Cut ½ lb sliced pork belly into 4-inch (10-cm) pieces and set aside.
If you rested the base batter for an hour or longer, take it out from the refrigerator. Add 4 large eggs (50 g each w/o shell), ½ cup tenkasu/agedama (tempura scraps), and two-thirds of the pickled red ginger to the bowl. Mix until combined.
Add the minced cabbage to the batter, one-third of it at a time. Mix well before each addition.
Prepare a large griddle or two large frying pans with lids to cook two savory pancakes at a time. In the pans, heat a bit of neutral oil on medium heat.
When it‘s hot (400ºF or 200ºC), add one portion of the batter to each pan. Using spatulas, spread and shape the batter in a circle about 6 inches (15 cm) in diameter.
Place 3 slices of pork belly on top of each okonomiyaki and cook, covered, on medium-low heat for 5 minutes.
When the bottom side is nicely browned, flip them over. Gently press the okonomiyaki to fix their shape and keep them together. Cook, covered, for another 5 minutes.
Flip them over one last time and fix their shape. Then cook, uncovered, for 2 minutes.
Transfer the cooked okonomiyaki to individual plates. Continue cooking the rest of the okonomiyaki.
Combine 3 Tbsp sugar, ¼ cup (4 Tbsp) oyster sauce, ½ cup (8 Tbsp) ketchup, and 7 Tbsp Worcestershire sauce in a small bowl. Mix all together until the sugar is completely dissolved.
Now, it‘s time to customize your okonomiyaki with the condiments and toppings of your choice.
