"I followed the Messenger of Allah ﷺ when he was riding, and I placed my hand on his foot and said : O Messenger of Allah, teach me Surah Hud and Surah Yusuf. He said: 'You will never recite anything greater before Allah than: "Say: I seek refuge with (Allah), the Lord of the daybreak." And "Say: I seek refuge with (Allah) the Lord of mankind.'" (Using translation from Nasāʾī 953)
أَنَّهُ قَالَ اتَّبَعْتُ رَسُولَ اللهِ ﷺ وَهُوَ رَاكِبٌ فَوَضَعْتُ يَدَيَّ عَلَى قَدَمَيْهِ فَقُلْتُ أَقْرِئْنِي مِنْ سُورَةِ يُوسُفَ فَقَالَ لَنْ تَقْرَأَ شَيْئًا أَبْلَغَ عِنْدَ اللهِ مِنْ قُلْ أَعُوذُ بِرَبِّ الْفَلَقِ