The Akshay Parta was given to Pandavas by Surya Dev.
When Pandavas went into exile, many Brahmins and priests followed them into the forest. Also, many guests came to meet them in the forest.
Pandavas managed to feed themselves, the Brahmins and the guests through the Akshay Patra given to them by Surya Dev. It provided them unlimited food and will stop only when Draupadi has have her food who usually ate last after feeding everyone else.
It was Lord Krishna who helped Pandavas by eating the last grain of rice from the Akshay Parta when Duryodhan cunningly sent Rishi Durvasa along with his many pupils to Pandavas at finish of lunch time.