Musnad Abu Ya'la al-Mawsili 42:226

Zuhayr narrated to us, Abu Mu'awiyah narrated to us, from al-A'mash, from Abu Salih, from Abu Sa'id or from Abu Hurayrah—al-A'mash was in doubt—who said: When the expedition of Tabuk took place, the people were struck by famine. They said, "O Messenger of Allah, if you would permit us, we would slaughter our camels used for carrying water, so we would eat and anoint ourselves [with their fat]." The Messenger of Allah (ﷺ) said to them, "Do so." Then Umar came and said, "O Messenger of Allah, if they do that, the riding animals will be few. Rather, call them to bring the remnants of their provisions, then invoke Allah for blessing upon them. Perhaps Allah will place blessing in that." The Messenger of Allah (ﷺ) said, "Do so." The Messenger of Allah (ﷺ) called for a leather mat and spread it out. Then he called for the remnants of their provisions. A man would come with a handful of corn, another with a handful of dates, and another with a piece of bread, until a quantity of that had gathered on the mat. He invoked blessing upon it, then said, "Take [it] into your vessels." They took [it] into their vessels until they did not leave a single vessel in the camp without filling it. They ate until they were full, and there remained a surplus. The Messenger of Allah (ﷺ) then said, "I bear witness that there is no god but Allah and that I am the Messenger of Allah. No servant meets Allah with this, without doubting, but he will be veiled from Paradise."