I have researched this for a few days now, and I haven't been able to find anything.
You can see in the top right, the recommendation plugin is there. The documentation for the plugin says "Place the code for your plugin wherever you want the plugin to appear on your page." but I can't manually put stuff in the right panel (right?). So I was thinking that maybe there was an admin setting to show the plugin, but after rigorous searching I could not find anything.
Does anyone have any ideas that can point me in right direction?
The recommend plugin at https://developers.facebook.com/docs/reference/plugins/recommendations is for external websites only. The recommend box on right of a Facebook page is auto generated to newer users in your fan base, or just randomly when content is needed for fill.