How was penicillin first made?

In 1928 Dr Alexander Fleming returned from a holiday to find mould growing on a Petri dish of Staphylococcus bacteria. He noticed the mould seemed to be preventing the bacteria around it from growing. He soon identified that the mould produced a self-defence chemical that could kill bacteria.

What food did penicillin come from?

Some of the fungi most frequently isolated from fermented and cured meat products such as Penicillium chrysogenum and Penicillium nalgiovense are known penicillin producers; the latter has been shown to be able to produce penicillin when growing on the surface of meat products and secrete it to the medium.