Food fraud is a global issue, which not only defrauds the consumer, but presents a food safety risk. Seafood is one of the most adulterated foods due to the vast and complex supply chains. Over the past 20 years, 236 original DNA-based assays have been published for the authentication of commercial species of fish. qPCR has been the most researched DNA-based authentication method, followed by DNA sequencing. The target genes cytb (cytochrome b) and COI (cytochrome c oxidase 1) are also the most researched in the literature. However, in silico testing on a select set of published assays showed a lack of assay reliability. A total of 77.78% of the tested assays were found to be non-specific. A novel DNA-based authentication method, using qPCR and closed-tube barcoding technology, called FASTFISH-ID, can provide a quick and reliable, first-screening step, in fish authentication.