Mishkat al-Masabih 13 Marriage كتاب النكاح 131

وَعَنْهُ قَالَ: إِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ أَعْتَقَ صَفِيَّةَ وَتَزَوَّجَهَا وَجَعَلَ عِتْقَهَا صَدَاقَهَا وَأَوْلَمَ عَلَيْهَا بحيس. مُتَّفق عَلَيْهِ

He said that God’s Messenger set Safiya free and married her, making her freedom her dower, and he held a wedding-feast for her with hais (A dish made of dates mixed with clarified butter and dried curd, kneaded and rubbed together. Sometimes flour was added.) (Bukhari and Muslim.)