adapted slightly from Meilleur du Chef
1.2 kg potatoes
2 small onions, sliced thinly
2 tablespoons of creme fraiche
200 g. of seiten (I got smoked seiten), in small cubes
1 cup white Savoie wine (optional)
2 Tbs. butter
1. Scrub the potatoes and place in a pot and cover completely with cold water. Put on medium-high heat, and boil until a fork slides easily through the potatoes.
2. Pre-heat oven to 430 F (220 C).
3. Heat a frying pan on medium-high heat, melt the butter, then add the onions and a pinch of salt. Cook for 10 minutes, then add the seiten and cook until onions are caramelized and seiten is caramelized on some sides, stirring time to time.
4. Cut potatoes into 1/2" thick slices width-wise, and cover the bottom of a gratin dish and sprinkle with pepper. Spoon half of the onion/seiten mix over the potatoes, drizzle 1 Tbs of the creme fraiche over then place the rest of the potatoes on top, sprinkle some more pepper, then put the rest of the onions, and the last 1 Tbs. of creme fraiche.
5. Cut the reblochon in half lengthwise, and place on top of everything (cutting into shapes so there isn't reblochon overlapping, if possible). If using, pour the cup of wine over the top.
6. Bake for 20 minutes, until reblochon is melted and bubbly on top.