Add recipe rich pin meta data to your ZipList recipes for enhanced pins on Pinterest.
The first time you use the rich pin validator, you'll need to apply for rich pins with Pinterest.
Click "Apply Now" and enter your domain name without the "http://" (i.e. "myawesomesite.com").
Make sure to select the data format "HTML Tags", then click "Apply Now". At this point you'll need to wait for approval from Pinterest by email.
After you've been approved by Pinterest, you can revisit any validation link again to check.