a type of foodstuff made by mixing sugar, peanut butter, and creamer packets in an uncovered metal cup of some kind then heating with a butane cigarette lighter for a couple minutes- these ingredients are all found in various Meals Ready to Eat (and on the floor of most people's cars but that's beside the point)- hence the name, MRE Cookies
Guy #1- What the fuck are you burning in the back seat of my car?!
Guy #2- Nothing's burning! I'm making some MRE Cookies from the shit I found near the back of this piece of shit Buick.
Guy #1- Hey! If you're gonna insult my car, you can fucking walk!