Sugar turned brown
Caramel is what you get when sugar is heated until it browns. The same process makes caramel coloring, one of the oldest and most used food colors. Its shade runs from pale yellow through amber to dark brown. Brewers in the 1800s were the first to make it on a large scale. Today it goes into cola, beer, whisky, gravy and many other foods. In Europe it carries the food code E150, as the Wikipedia article on caramel coloring explains.
Light caramel or dark?
The #AF6F09 on this page is a golden amber brown. It matches "caramel" in the 2010 xkcd color survey, where web users named colors they saw on screen. Wikipedia's alphabetical list of colors gives Caramel as #65350F, a much darker brown. It links to an article on the color that does not exist, so no source backs that code.
Nearby candy colors on this site are butterscotch and toffee. Golden brown is also close.

