Qatada asked Anas which Supplication Allah's Messenger (ﷺ) frequently made. He said:

The supplication that he (the Prophet (ﷺ) made very frequently is this:" O Allah, grant us the good in this world and the good in the Hereafter and save us from the torment of Hell-Fire." He (Qatada) said that whenever Anas had to supplicate he made this very supplication, and whenever he (intended) to make another supplication he (inserted) this very supplication in that.

حَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا إِسْمَاعِيلُ، - يَعْنِي ابْنَ عُلَيَّةَ - عَنْ عَبْدِ الْعَزِيزِ، - وَهُوَ ابْنُ صُهَيْبٍ - قَالَ سَأَلَ قَتَادَةُ أَنَسًا أَىُّ دَعْوَةٍ كَانَ يَدْعُو بِهَا النَّبِيُّ صلى الله عليه وسلم أَكْثَرَ قَالَ كَانَ أَكْثَرُ دَعْوَةٍ يَدْعُو بِهَا يَقُولُ ‏

‏ اللَّهُمَّ آتِنَا فِي الدُّنْيَا حَسَنَةً وَفِي الآخِرَةِ حَسَنَةً وَقِنَا عَذَابَ النَّارِ ‏

‏ ‏.‏ قَالَ وَكَانَ أَنَسٌ إِذَا أَرَادَ أَنْ يَدْعُوَ بِدَعْوَةٍ دَعَا بِهَا فَإِذَا أَرَادَ أَنْ يَدْعُوَ بِدُعَاءٍ دَعَا بِهَا فِيهِ ‏.‏