This is ultimate Japanese comfort food. It would be really good with sake or beer, and I think that's why it is commonly served at Izakaya. In Tokyo, there are restaurants that specialize in Okonomiyaki (like my personal favorite, Chibo Okonomiyaki, in Ebisu). This is also good served with salad or daikon salad.
I was impressed that on my first try (see photo above)- it tasted better than the kinds I have had in the States. Still working on topping the specialized Okonomiyaki restaurants in Tokyo, but this is very very close.
Prepare the sauce ahead and cut/prep the fillings first before making the batter.
Feel free to double the sauce recipe!
Simmer on low boil for 3 minutes:
1/4 C ketchup
1.5 TB worcestershire sauce
1/4 Tea mustard
2 TB mirin
1 TB sugar
1 tea soy sauce
Prepare ¼ C mayonaise in a squeeze bottle or pastry bag fitted with a round hole tip. Set aside.
mochi (kiri mochi block type, cut into 1/4 inch cubes)
napa cabbage (or perhaps savoy might work), hand cut (don't use a shredder b/c it will be too thin and watery)- use 2-4 cups until the dough isn't soggy
2 TB beni shoga (picked ginger), diced or cut into strips
1/2 C thinly sliced green onion or Naganegi
Pick some optional fillings:
shiitake, button/cremini or chanterelle mushrooms
cheddar cheese (cut into 1/4 inch cubes or smaller)
thinly sliced beef, cut into strips
shrimp (deveined & sliced in half or chunks)
Make the batter
Mix together, beating out lumps, only adding as much water as is needed to form batter:
1 C cake flour
<= 1 C dashi (or water)
1/2 tea salt
4 - 5 TB grated yamaimo or nagaimo (strange root vegetable from japan, looks like hairy daikon) - grate using large box grater-- it will become gooey liquid.
Now mix in the fillings into the batter. You want to have a thick mass with the fillings, so it should not be liquidy. If it is still got liquid, add more cabbage or other fillings.
Preheat a pan on the stove to medium hot. Pour in just enough oil to coat the bottom of the pan. Ladle in batter/filling mixture- make the size manageable for flipping (which can depend on the size of your spatula).
Flip to cook the other side and layer a couple slices Japanese thin sliced pork (buta bara usugiri type- looks like thin bacon) on top. Cover, cook until both sides and bacon is done.
Spread tonkatsu/okonomiyaki sauce generously over the top of the bacon side. Squeeze mayonnaise in squiggle lines across the top of the sauce. Then sprinkle katsuobushi (fish flakes) and aonori (green/blue seaweed powder) on top and enjoy!