Is buuz (Mongolian dumplings) a countable noun, or uncountable noun? If the former, how do you pluralise it?
I tried looking up the term in onelook.com and only got a hit for Wikipedia, not for any dictionaries.
They are countable though I tend to lose count when eating them!
бууз (buuz, dumplings) is the plural for банш (bansh, dumpling), and appears to be irregular not using -гууд or -нууд to form the plural.
My guess is банш at one point was pluralised to баншнууд which then became shortened to бууз because the en-sh-en (ншн) is difficult and which also contributed to the change from de (д) to ze (з) at the end.
As far as I can tell from reviewing more than a dozen Google entries, the plural of "buuz" is "buuz." The Wikipedia article you cited repeatedly refers to "buuz" as a plural noun. "Buuz" are mutton-filled Mongolian dumplings (although beef is sometimes used instead of mutton). To confirm this usage, you may have to ask someone at a Mongolian restaurant!