Candy Bar Riddle

I was going to cut Austin's hair last night so he could look handsome for the fam and I said, "Austin do you want a candy to eat while I cut your hair?" (I bribe my kids...I'm cool with it). He says, "Yeah mom I want a 'Little Thumb.' I said, "Austin I don't know what a 'Little Thumb' is. He says, "Yes you do, it has a yellow wrapper, blue writing, that crunchy peanut stuff, with chocolate on the outside."

Now can you guess what a 'Little Thumb' is.  When I figured it out I laughed my head off! I love love love his brain!