A description for something that is extremely good, most commonly used to describe good food. Can also be used in the form "pengest" (as in, 'the pengest food is chicken').
ALFIE: Oi have you tried those chicken wings from that new place?
GRIFFIN: Ah yea they're so good bro!
ALFIE: Absolutely! They're peng mate!
GRIFFIN: Chicken wings are the pengest munch out there!
Really nice weed, usually high grade in the form of cheese, haze or kush. Can also be used to describe anything of exceptional quality, including people, but primarily it is a weed term.