Our Geo Quiz today took us to a north African nation, with a tradition of aging butter.

That country is Morocco.

And the ripe butter is called smen. Smen is hard to find here in the U.S. But it's a vital ingredient for Moroccan cooking.

Its flavor is layered with salt, herbs and time. Lots of time. You have to let this butter sit for about 6 weeks.

Cookbook author Paula Wolfert knows all about it.