This is book number 38 in the Nancy Drew Notebooks (Pb) series.
CARAMEL, CHOCOLATE --
A MISSING CANDY
FORMULA MAKES A
What could be sweeter than a visit to Zuckerman's Zonked Candy Factory? Nancy and her class will see how their favorite candy is made, and even get free samples. Mr. Zuckerman himself gives the grand tour past the sparkling machines that spit out Sticky Gummy Goo, Karamel Krunchettes, Frostee Jewels, and more.
Then Mr. Zuckerman tells the kids he has dreamed up the perfect candy. He even shows them the paper with the secret recipe. But when the visit is over, the recipe has disappeared and no one can find it Is the greatest candy lost for good?