And if he forgets to say 'Bismillaah', let him say -
بِسْمِ اللَّهِ أَوَّلَهُ وَآخِرَهُ
Pronunciation
Bismillaahi 'awwalahu wa 'aakhirah
Meaning
In the name of Allah, in the beginning and in the end.
Source: Sahih. Abu Dawud: 3767
Read the hadith
حَدَّثَنَا مُؤَمَّلُ بْنُ هِشَامٍ، حَدَّثَنَا إِسْمَاعِيلُ، عَنْ هِشَامٍ، - يَعْنِي ابْنَ أَبِي عَبْدِ اللَّهِ الدَّسْتَوَائِيَّ - عَنْ بُدَيْلٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُبَيْدٍ، عَنِ امْرَأَةٍ، مِنْهُمْ يُقَالُ لَهَا أُمُّ كُلْثُومٍ عَنْ عَائِشَةَ، - رضى الله عنها - أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا أَكَلَ أَحَدُكُمْ فَلْيَذْكُرِ اسْمَ اللَّهِ تَعَالَى فَإِنْ نَسِيَ أَنْ يَذْكُرَ اسْمَ اللَّهِ تَعَالَى فِي أَوَّلِهِ فَلْيَقُلْ بِسْمِ اللَّهِ أَوَّلَهُ وَآخِرَهُ " .
Narrated Aisha, Ummul Mu'minin: The Messenger of Allah (ﷺ) said: When one of you eats, he should mention Allah's name; if he forgets to mention Allah's name at the beginning, he should say: "In the name of Allah at the beginning and at the end of it." [Sahih (Albani). Abu Dawud: 3767]
Duas from IslamicAPI's Masnun Dua dataset (based on the Quran, hadith, Hisnul Muslim and Rahe Belayat). See the dataset