It's a traditional tofu dish called hiyayakko. Chilled tofu is simply served with various toppings. They can be a wide variety of fresh or cooked ingredients of your choice. Common toppings are katsuobushi (dried bonito flakes), grated ginger, green onion, shiso (perilla), and so on. I like to use silken tofu for this dish. When it's too hot to cook, hiyayakko is a quick appetizer to prepare.
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