Ali bin Abu Talib reported,
The Messenger of Allah ﷺ said, "Allah 
says, 'Fasting is for Me, and I alone reward it.' The fasting person has two moments of joy, one when he breaks his fast and another when he meets his Lord. By the One in whose hand my soul rests, the smell of the fasting person's breath is more pleasing to Allah than the fragrance of musk."
Nasai 2213
Sahihأخبرني هلال بن العلاء قال حدثنا أبي قال حدثنا عبيد الله عن زيد عن أبي إسحق عن عبد الله بن الحارث
عن علي بن أبي طالب
عن رسول الله ﷺ قال إن الله تبارك وتعالى يقول الصوم لي وأنا أجزي به وللصائم فرحتان حين يفطر وحين يلقى ربه والذي نفسي بيده لخلوف فم الصائم أطيب عند الله من ريح المسك
[Sahih] Bazzar narrated it in Bahr Zakhkhar, 3/129, no. 915, from Hilal bin Ala bin Hilal bin Umar, with this chain, and it is in Kubra, no. 2521. This hadith has many corroborating narrations, see nos. 2215, 2216, and others.Zayd is Ibn Abu Unaysah, and Ubaydullah is Ibn Amr Raqqi. Nasai commented on this hadith, but his comment is outweighed by other evidence.