Phoenix buns, also known as salted egg custard buns, liu sha bao, or lava buns, are a popular dim sum dish from Guangdong that feature a creamy, salted egg yolk filling in a soft, fluffy white bun. The buns are sweet and savory, with a unique flavor that comes from the contrast between the salted egg and the added sugar. When broken apart, the egg yolk custard oozes out.