Raindrop cake is a dessert made of water and agar (a gelatin-like substance) that is supposed to resemble a raindrop. It first became popular in Japan in 2014, and later gained international attention. Originally a Japanese dessert is known as "Mizu Shingen Mochi", the dish is an evolution of the traditional Japanese dessert "Shingen Mochi".

The dish is made from mineral water and agar; thus, it has virtually no calories. The water from the original dish was obtained from Mount Kaikoma of the Southern Japanese Alps, and it has been described as having a mildly sweet taste. The agar is a vegetarian/vegan alternative to gelatin that is made from seaweed. After being heated, it is molded and cooled. A molasses-like syrup, called "kuromitsu", and soybean flour, called "kinako", are used as toppings. The dish appears like a transparent raindrop, although it has also been compared to breast implants and jellyfish.

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