Mustadrak al-Hakim — Hadith 8448

It is narrated from Umm al-Mundhir al-Adawiyyah (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) came to me, and with him was Sayyiduna Ali (may Allah be pleased with him), who had only just recovered from an illness (and was still weak). She said: We had some bunches of dates hanging up. The Messenger of Allah (peace and blessings be upon him) began to eat from them, and Sayyiduna Ali (may Allah be pleased with him) also began to eat. So the Prophet (peace and blessings be upon him) said: "Stop, O Ali! You are still in a state of weakness." She said: So Sayyiduna Ali (may Allah be pleased with him) stopped, while the Prophet (peace and blessings be upon him) continued eating from it. Then I prepared chard and barley for them, and the Prophet (peace and blessings be upon him) said: "O Ali! Now eat from this."
This hadith has a sahih (authentic) chain of narration, but the two Shaykhs (Bukhari and Muslim) did not record it.