Aonori

Raw Aonori (from Lake Hamana)

Okonomiyaki with aonori topping (the green powder)

Aonori (青海苔 or アオノリ^?, lit. "blue seaweed" or "green seaweed"), also known as green laver, is a type of edible green seaweed, including species from the genera Monostroma and Enteromorpha of Ulvaceae. It is commercially cultivated in some bay areas in Japan, such as Ise Bay. It contains rich minerals such as calcium, magnesium, lithium, vitamins, and amino acids such as methionine.
It is used in its dried form for Japanese soups, tempura, and material for manufacturing dried nori and tsukudani. It is also used in a powdered form, often blended with Ulva species of Ulvaceae as its production is limited.
It is used commonly for flavouring of some Japanese foods, usually by sprinkling the powder on the hot food, for its aroma:

• Fried noodles (Yakisoba or Yakiudon)
• Okonomiyaki (Japanese pancake)
• Takoyaki (octopus dumpling ball)
• Isobe age
• Isobe mochi
• Shichimi (7-spices seasoning)
• Japanese Potato chips
• Misoshiru