Jr. Girl Scout #1: (about Michael's peanut butter chocolate candy) Those, um, kinda taste like Tagalongs.
Christopher: Whose cookies are those?
Michael: Not mine! I'm not taking credit for 'em.
She is referencing one of the eleven different cookies girl scouts of all types sell each year. The Tagalong is a chocolate-covered cookie with a layer of peanut butter inside, which is why Michael's candy reminds her of it, and why he refuses to take responsibility for producing the equivalent of a boxed cookie.