Musnad Abu Ya'la al-Mawsili 150:54

Muhammad ibn Abdullah ibn Numayr narrated to us, Yunus ibn Bukayr narrated to us, Hisham ibn Urwah narrated to us, from his father, from Aisha, who said: My mother used to treat me with fat, wanting to make me enter upon the Prophet, may Allah bless him and grant him peace, but that did not succeed for her until I ate fresh dates with cucumbers. Then I gained weight in the best of ways.