This was a short story I read in middle school, 5-7 years ago, I don’t remember if it was in a book or magazine, but it was not online. It was horror story about a teenaged girl who sets a trap for a man who has been abusing local kids. The main thing I remember is that somehow this trap involved making him a ‘sugar cream pie” but I can’t remember if it was posioned or if it somehow trapped him some other way. I would really like to find this story and read it again, thanks!
Lost Classics of Teen Lit: Name That Book! 
I think you are referring to “The Creep.” The girl was small and looked young for her age and helped the police department by dressing as a little girl in order to help the police nab chester the molester, who turned out to be the affluent owner of a local car dealsrship.
LikeLike
Oh, the author is Susan Dodson.
LikeLike
Oh, definitely The Creep. The girl works with the police department because although she is older, she looks really young and with the right hairstyle and makeup, she looks like she is, I don’t know, 10 or 12. She is in love with a boy named Garrett who sees her in her disguise and she feels really embarrassed.
The titular creep turned out to be a car dealer in the area. She recognizes him, he grabs her and drags her off to one of his cars and her grandpa saves the day by strangling him with his pocket watch chain. Of course.
LikeLike