Scanning multiple pages into one image file

Using an Office Jet Pro 8600 Plus printer, I have installed the software and can print and scan.  However, I am trying to scan family recipes from a two-sided index card, but the end result is two separate image files (e.g. Cream Pie001 and Cream Pie002).

I have downloaded and reviewed the online User's Guide, but it does not speak to manually imaging two-sided documents (only speaks to using the ADF).

Question: What is the process to follow that will allow me to scan a two-sided index card and save as one image file?

Thanks!

Gman--