Assalamu 'alaykum can you please clarify this hadith:Allah's Messenger said: "Wudu is (required) from what fire has touched, even if it be a piece of cheese."are we to do wudu after eating anything which fire has touched? May Allah reward you, ameen.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

We could not find the wording you mentioned in the question.

What is reported in this regard is the narration about Abu Hurayrah, and that he performed Wudhoo’ and then said: "I am performing Wudhoo’ because I ate a cooked Aqit (dried meat cooked with barely or wheat) because I heard the Messenger of Allah saying: 'Perform Wudhoo’ after eating anything cooked.'" [Muslim]

Therefore, the command to perform Wudhoo’ after eating anything cooked is confirmed. However, it was either abrogated, or the command in the narration does not indicate that the matter is mandatory. This is because there are narrations reported by Al-Bukhaari and Muslim stating that the Messenger of Allah ate cooked food and then prayed without performing Wudhoo’.

Hence, it is not an obligation to perform Wudhoo’ after eating something cooked. An-Nawawi conveyed the consensus of the scholars regarding this matter saying: "The difference of opinion regarding this matter was in the early generations, but then later the Muslim scholars have agreed in consensus that it is not mandatory to perform Wudhoo’ after eating something cooked."

Ibn Qudaamah said in his book Al-Mughni: “It is not mandatory to perform Wudhoo’ after eating anything cooked other than the meat of camels; this is the saying of the majority of the scholars. This was reported on the authority of the four rightly guided caliphs, Abay ibn Ka’b, Ibn Mas’ood, Ibn ‘Abbaas, ‘Aamir ibn Rabee’ah, Abu Ad-Dardaa’, Abu Umaamah and the majority of the Jurists. I do not know of any difference in opinion about this issue.”

Allah knows best.