The act of going literally insane over brownies. Similar to what the Cookie Monster looks like when eating cookies. Just chowin' down on those mofo'ing brownies, crumbs falling down your face and all. Don't stop until you're full.
"Yo, did you see JerBear in class today?"
"Yeah son--brownie beast mode was in full effect!"
"That guy goes crazy over brownies!"
"Yup, SA."
by BowseyLove September 12, 2013
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