The Messenger of Allah ﷺ would break his fast with fresh dates before praying. If fresh dates were not available, he would break it with dried dates, and if those were not available either, he would take a few sips of water.
حدثنا أحمد بن حنبل حدثنا عبد الرزاق حدثنا جعفر بن سليمان حدثنا ثابت البناني أنه سمع
كان رسول الله ﷺ يفطر على رطبات قبل أن يصلي فإن لم تكن رطبات فعلى تمرات فإن لم تكن حسا حسوات من ماء
[Its isnad is hasan] Tirmidhi narrated it in the Book of Fasting, Chapter on What Is Recommended to Break the Fast With, no. 696, from the hadith of Abdul-Razzaq, through him, and he said, hasan gharib. It is also in Musnad Ahmad, 3/164. Daraqutni graded it sahih, 2/185, as did Hakim, according to the standard of Muslim, 1/432, and Dhahabi agreed with him.