tōng bāau
tong1 baau1
湯 is soup, and 包 is bun, so 湯包 is soup bun.
Soup dumplings are not dumplings in soup, but the reverse, steamed buns filled with soup. Of the many varieties of soup dumplings, the most common one in dim sum restaurants is Shanghai dumplings.
Shanghai dumpling
chocolate Shanghai dumpling