“We went out with the Messenger of Allah (ﷺ) on the campaign of Khaibar, and in the evening the people lit their fires. The Prophet (ﷺ) said: ‘What are you cooking?’ They said: ‘The meat of domesticated donkeys.’ He said: ‘Throw out what is in them (the pots) and break them.’ A man said: ‘Or can we throw out what is in them and wash them?’ The Prophet (ﷺ) said: ‘Or (do) that.’”
Sunan Ibn Majah Book 27, Hadith 34