It is usually made with small pieces of octopus, which is called tako in Japanese. But of course it can be made with pretty much anything you want, from kimchi (Korean spicy cabbage) to almonds or vegetables. Recipes are made to be modified!
Takoyaki parties with friends are very common here. Those machines to make octopus balls are super cheap and the ingredients are super basic, only there is a particular “takoyaki flour” with a special taste to it. There is also a special takoyaki sauce which is spread over them, along with mayonnaise and negi (green onion). Other things can be sprinkled on top, such as matcha (green tea) salt, ginger, pepper, etc.
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