Is it permissible to prepare food and donate its reward to the deceased as charity?

Preparing and distributing food with the intention that its reward be for the deceased is permissible, and it is a type of charity whose reward reaches the deceased by scholarly consensus. This is supported by the hadith of Sa'd ibn 'Ubada and 'Aisha (may Allah be pleased with them) concerning their questioning the Prophet (peace be upon him) about giving charity on behalf of the deceased, to which the Prophet (peace be upon him) affirmed it.

It is not a condition that the food be something the deceased loved. Rather, the consideration in charity is what the giver loves and holds dear, for Allah Almighty says: ﴿You will not attain piety until you spend from that which you love.﴾ Charity benefits the deceased, and it is hoped that the giver will receive a reward similar to that of the deceased.