Sunan Ibn Majah
3332
Sahih+3

It was narrated from Sa’d, the freed slave of Abu Bakr – and Sa’d used to serve the Messenger of Allah (ﷺ) and he liked this Hadith – that the Prophet (ﷺ) forbade eating two dates at once

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi