The Prophet ﷺ passed away at a time when we had our fill of the two black things, dates and water. In another wording, when the people had their fill.
توفي النبي ﷺ حين شبعنا من الأسودين: التمر والماء. وفي لفظ: حين شبع الناس.
Bukhari narrated it in the Book of Foods (5383), and Muslim in the Book of Asceticism (30:2875), both through Mansur bin Abdul-Rahman Hijbi, from his mother Safiyyah, from Ayesha, who said, and then narrated it, the first wording being Bukhari's and the other wording being Muslim's.