Hadith 31-114

وَبِهذَا الإِسنادِ قالَ: قالَ الحُسَيْنُ بْنِ عَلِى‏عَلَيْهِمَا السَّلاَمُ: كانَ النَّبِيُ‏ صَلَّى اللهُ عَلَيْهِ وَآلِهِ إِذا أَكَلَ طَعاماً يَقُولُ: اَللَّهُمَّ بارِك لَنا فِيهِ وَارزُقنا خَيْراً مِنْهُ، وَإِذا أَكَلَ لَبَناً أَوْ شَرِبَهُ يَقُولُ: اَللَّهُمَّ بارِك لَنا فيهِ وَارزُقنا مِنْهُ.

According to the same documentation, it is narrated that Al-Husayn ibn Ali (a.s.) said, “The Prophet (S) said the following after he ate: O my God! Grant us blessings in this meal and make some better food our sustenance.” When he (a.s.) ate milk or yoghurt he said, O my God! Grant us blessings in this meal and make it our sustenance.”