اللَّهُمَّ بَارِكْ عَلَى مُحَمَّدٍ وَعَلَى آلِ مُحَمَّدٍ كَمَا بَارَكْتَ عَلَى إِبْرَاهِيمَ وَعَلَى آلِ إِبْرَاهِيمَ إِنَّكَ حَمِيدٌ مَجِيدٌ
Transliteration
Allahumma barik 'ala Muhammadin wa 'ala ali Muhammadin kama barakta 'ala Ibrahima wa 'ala ali Ibrahima innaka hamidun majid
English meaning
O Allah, send blessings upon Muhammad and the family of Muhammad, as You sent blessings upon Ibrahim and the family of Ibrahim. Verily You are full of praise and majesty.
When is it recited?
Recited right after Allahumma salli in the final sitting of the prayer. It is also recited after the second takbir of the funeral prayer.
Source
Bukhari, Anbiya 10, 3370