A "PF cake" is named after its "creator", p
It is a mushroom growing substrate prepared of brown rice flour (BRF), vermiculite, and water, spooned loosely into a glass 1/2 pint jar, and inoculated with a spore syringe.
It is often referred to as the "PF style," "PF method," etc. Generally these terms refer to the substrate recipe and the style of inoculation (the creation of the colonized/colonizing substrate).
Please refer to the Basic Cultivation Guides
for detailed overviews of the "PF" method, including substrate recipes, inoculation methods, colonization parameters, and the like.