Hot pot seems to have originated in Mongolia where the main ingredient was meat, usually beef, mutton or horseflesh.

火锅似乎起源于蒙古，在那里主要配料是肉，通常是牛肉，羊肉或马肉。

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When people eat the mutton hot pot, the concentrated soup only needs to be put into the boiled water in a pot and evenly stirred, and the vacuum-packaged mutton is put into the pot.

人们食用时只须把浓缩液汤汁倒入锅里开水中搅匀，再把真空包装里的羊肉倒入锅中即可。

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Mrs. Brown: I hear that mutton in a hot pot with some herbs is very delicious.

布朗太太：听说羊肉炖中药材味道很好。

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The media earlier revealed a criminal ring that had been selling rat, fox and mink meat bought from farms in Shandong as mutton for hot-pot restaurants in Shanghai and neighbouring Wuxi since 2009.

BBC: China media: Fake food scandals