And the evidence that the Prophet, peace and blessings be upon him, was only asked: "We have learned how to greet you with peace, but how should we send prayers upon you in the tashahhud?"

Sayyiduna Abu Mas’ud Uqbah bin Amr (may Allah be pleased with him) narrates that a man came and sat in front of the Messenger of Allah (peace and blessings be upon him) while we were also present in his service. He said,“O Messenger of Allah, we have learned how to send salam upon you, but when we wish to send salat (blessings) upon you in our prayer, how should we do so? May Allah send mercy upon you.”He says that (upon this question) the Messenger of Allah (peace and blessings be upon him) remained silent for a while until we wished that (perhaps) this person had not asked you. Then the Prophet said:“When you wish to send salat upon me, then say «‏‏‏‏اللّٰهُمَّ صَلِّ عَلىٰ مُحَمَّدِ النَّبِيِّ الْأُمِّيِّ وَعَلىٰ آلِ مُحَمَّدِ كَمَا صَلَّيْتَ عَلىٰ إِبْرَاهِيمَ، وَعَلى آلِ إِبْرَاهِيمَ وَبَارِكْ عَلىٰ مُحَمَّدِ النَّبِيِّ الْأُمِّيِّ وَعَلىٰ آلِ مُحَمَّدِ كَمَا بَارَكْتَ عَلىٰ إِبْرَاهِيمَ وَعَلىٰ آلِ إِبْرَاهِيمَ، إِنَّكَ حَمِيدٌ مَجِيدٌ» ‏‏‏‏ (O Allah, send mercy upon Muhammad, the unlettered Prophet, and upon the family of Muhammad, just as You sent mercy upon Ibrahim and upon the family of Ibrahim. And send blessings upon Muhammad, the unlettered Prophet, and upon the family of Muhammad, just as You sent blessings upon Ibrahim and upon the family of Ibrahim. Surely, You are Most Praiseworthy, Most Glorious).”