It is narrated from Sayyidah Safiyyah (may Allah be pleased with her) that she said: "The Messenger of Allah (peace and blessings be upon him) came to my home, and I presented to him (peace and blessings be upon him) cold meat of a (sheep's) shoulder; I was preparing it for him (peace and blessings be upon him) by scraping it off the bone and cleaning it. So he (peace and blessings be upon him) ate it, and then (without performing a fresh ablution after eating something cooked on fire) stood up and prayed."
Imam al-Tirmidhi narrated this hadith in 'al-Shama'il al-Muhammadiyyah' (171), as did Imam Ahmad bin Hanbal (26391) and Imam al-Nasa'i (184). Regarding the narrator in its chain, Ishaq al-Hashimi, the Imams have voiced criticism about his reliability; however, the ruling that eating something cooked on fire does not break ablution is established by other most authentic hadith.
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب الطهارة / 132
Hadith Gradingمحدثین:إسناده حسن
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :إسناده حسن لذاته. » «أخرجه مجمع الزوائد ومنبع الفوائد برقم: 1333، وأخرجه إتحاف الخيرة المهرة بزوائد المسانيد العشرة برقم: 636»