Sweet Potato Fries: An Experiment Gone Not-Quite-Right

A while back, we decided to make sweet potato fries, based on this recipe from the NYTimes.  The idea is you start the potatoes in cold oil, warm the pan slowly, and cook at lower temperature until done.  No hot oil splattering on your stove and arms, no hot grease smell permeating the whole house.

So, we tried it: and it went well, for the most part.  Here are the sweet potatoes quietly bubbling away in their pan:

The thing is, though, that they don't look as golden brown in the oil as their really are after you remove them.  So, by the time we thought they were done (it took more than an hour) they were actually nearly burnt.  So, for future reference, this method works, but remove a fry or two occasionally to see how well browned they really are.