Welcome to Cake Picnic, Sydney edition. It's the viral event that's already sold out dates in San Francisco, New York and Los Angeles. Tickets in Dubai, London and Mexico City were harder to come by than a double-yolk egg. And now it's landed on Australian shores, with a Melbourne event earlier this month boasting 1,600 cakes in one sitting. "I had no idea that I could ever go on tour for cake," laughs Cake Picnic founder Elisa Sunga, part-time hobby baker and full-time Google employee specialising in AI. "People go on tour for music and whatnot, but for cake? "It just seems so whimsical and delightful to be able to do that." The concept is simple. Two years ago, Sunga - who moved to San Francisco aged 12 from her hometown of Baguio City in the Philippines - posted an online invitation for a small gathering with one request: everyone must bring a cake. The 35-year-old figured maybe a dozen or so people might turn up and brought seven cakes to make sure everyone would get a taste.…