allaahsavedus:

“Whoever ate something, then said: 

الْحَمْـدُ للهِ الَّذي أَطْعَمَنـي هـذا وَرَزَقَنـيهِ مِنْ غَـيْرِ حَوْلٍ مِنِّي وَلا قُوَّة

Al-Hamdu lillaahilladhee at’amanee hadha wa razaqneeh min ghayri hawlin minnee wa la quwwa

‘Praise be to Allah who has fed me this food and provided it for me, without any strength or power on my part’

is forgiven his past and future sins.

[‘Sahih al-Jami’ #6086]

(Source)