Upon breaking the fast

اللَّهُمَّ لَكَ صُمْتُ وَعَلَى رِزْقِكَ أَفْطَرْتُ

Allāhumma laka ṣumtu wa ʿalā rizqika afṭartu

O Allah, for You I have fasted, and with Your provision I have broken my fast.

Sunan Abī Dāwūd 2358: Ḍaʿīf (weak chain). The sound wording, Sunan Abī Dāwūd 2357, is in the Fasting collection.