When Messenger of Allah ﷺ conquered Khaibar, we caught hold of the asses outside the village. We cooked them (their flesh). Then the announcer of Messenger of Allah ﷺ made the announcement: Listen, verily Allah and His Messenger have prohibited you (the eating of) their (flesh), for it is a loathsome evil of Satan's doing. Then the earthen pots were turned over along with what was in them, and these were brimming (with flesh) at that time.  

لَمَّا فَتَحَ رَسُولُ اللَّهِ ﷺ خَيْبَرَ أَصَبْنَا حُمُرًا خَارِجًا مِنَ الْقَرْيَةِ فَطَبَخْنَا مِنْهَا فَنَادَى مُنَادِي رَسُولِ اللَّهِ ﷺ أَلاَ إِنَّ اللَّهَ وَرَسُولَهُ يَنْهَيَانِكُمْ عَنْهَا فَإِنَّهَا رِجْسٌ مِنْ عَمَلِ الشَّيْطَانِ فَأُكْفِئَتِ الْقُدُورُ بِمَا فِيهَا وَإِنَّهَا لَتَفُورُ بِمَا فِيهَا