Musnad Ahmad 1181:0

Narrated Umm al-Mundhir bint Qays al-Ansariyyah: The Messenger of Allah (ﷺ) entered upon us, and with him was Ali, who was recovering from an illness. We had hanging bunches of dates. The Messenger of Allah (ﷺ) stood up and began eating from them. Ali also stood up to eat, but the Messenger of Allah (ﷺ) said to Ali, "Stop, O Ali, for you are recovering." So Ali sat down, and the Prophet (ﷺ) continued eating. Umm al-Mundhir said: I then prepared some chard and barley. The Prophet (ﷺ) said, "O Ali, eat from this, for it is more beneficial for you."