Even after the delicious gratin, I had a few yukon gold potatoes left over. I decided to make oven-baked fries with them based on this idea from About.com. I think they turned out fabulous, though my execution was a little off. They'd do best elevated on a rack, and well separated (or at least checked on in the first 15 min to move them around a bit). Mine sat in the oven, untouched, for the whole time and I literally had one giant mass of fries when I was done. It was no problem separating them back to individual fries again, but it would have been nicer if they came out of the oven that way. :-) Anyway, they had a nice outer coating (not crunchy but not mush), and a lovely creamy center.
Oven Baked Fries
Source: Adapted from about.com
3 yukon gold potatoes, peeled or scrubbed well
2 egg whites
2-3 teaspoons of seasoning, your choice (I think I used some combo of garlic powder, paprika, mexican oregano)
Slice potatoes into 1/4" to 3/8" matchsticks. Beat egg whites to a light froth and gently fold in seasoning. Line a baking sheet with non-stick foil or spray with cooking spray. Dip potatoes in egg white mixture, then place in an single layer on the baking sheet. Bake at 425 for 35-40 minutes. Sprinkle with salt and enjoy!