bitch, if you don't shut your mouth, you're gonna get a big ol' grundlemuffin
the placing of one's fist into one's [grundle] and letting it bake there for a minute, then removing it and punching another person across the face with it
"bitch, if you don't shut your mouth, you're gonna get a big ol' grundlemuffin" What is the definition of "grundlemuffin"?