For the uninitiated, Dubai chocolate is a candy bar filled with pistachio and tahini cream and crispy pastry recently popularized by social media influencers. While it’s easy to dismiss as a viral craze now past its peak, the nutty green confection has spiked global pistachio demand, and growers and processors are ramping up production. That means more pistachios need to be tested for aflatoxins—a byproduct of a common crop mold.