It was narrated from Ibn 'Abbas that:

the Prophet (ﷺ) went out in Ramadan and fasted until he came to Qudaid, then a cup of milk was brought to him and he drank and broke his fast; he and his Companions.

أَخْبَرَنَا مُحَمَّدُ بْنُ حَاتِمٍ، قَالَ أَنْبَأَنَا سُوَيْدٌ، قَالَ أَخْبَرَنَا عَبْدُ اللَّهِ، عَنْ شُعْبَةَ، عَنِ الْحَكَمِ، عَنْ مِقْسَمٍ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم خَرَجَ فِي رَمَضَانَ فَصَامَ حَتَّى أَتَى قُدَيْدًا ثُمَّ أُتِيَ بِقَدَحٍ مِنْ لَبَنٍ فَشَرِبَ وَأَفْطَرَ هُوَ وَأَصْحَابُهُ ‏.‏