Aisha reported: We in the household of Muhammad, peace and blessings be upon him, used to live for a whole month without cooking anything over a fire. We would have nothing to eat but dates and water.
Source: Ṣaḥīḥ Muslim 2792
Grade: Sahih (authentic) according to Muslim
عَنْ عَائِشَةَ قَالَتْ إِنْ كُنَّا آلَ مُحَمَّدٍ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ لَنَمْكُثُ شَهْرًا مَا نَسْتَوْقِدُ بِنَارٍ إِنْ هُوَ إِلَّا التَّمْرُ وَالْمَاءُ
2792 صحيح مسلم كتاب الزهد والرقائق