a perfect side to any holiday meal, these potatoes were the first to christen the blade of our new mandoline. i think it’s safe to say that you could get away with thinly slicing the potatoes by hand, but why do that when you have a fun new toy to play with?
this dish comes together fairly simply, and was actually our first time working with leeks. they really are just as gritty as everyone on tv says they are, but we just soaked them really well in a bowl of cold water, and spun them dry in the salad spinner. problem solved.
5 Tbs. unsalted butter
4 lb. leeks, white and light green portions, rinsed well, cut into 1/4-inch rings
1 1/2 Tbs. kosher salt
1 tsp. minced fresh thyme
1/4 tsp. freshly grated nutmeg
3/4 tsp. freshly ground pepper
1 cup heavy cream
6 oz. Gruyère cheese, grated
3 oz. Parmigiano-Reggiano cheese, grated
3 lb. russet potatoes, peeled, cut into 1/4-inch slices
3 Tbs. minced fresh chives
1. in a dutch oven, or a large nonstick frying pan that can go in the oven, melt 4 tablespoons of the butter over medium heat. add leeks and salt. stir to coat leeks in butter. cover and cook, stirring every once and awhile, for about 20 minutes, until leeks are tender.
2. add thyme, nutmeg, pepper & cream, and simmer until thickened, about 15 minutes. transfer to a bowl and let cool a little bit. wipe out pan, and coat with the last tablespoon of butter.
3. preheat oven to 400°. in a separate bowl (or the paper plate you grated it onto), combine the cheeses. back in the pan, layer 1/3 of the potatoes. spread with 1/3 of the leek mixture (here we go with the fractions again. if i can do it, you can do it.). sprinkle 1/3 of the cheese on this, then 1 tablespoon chives. do this 2 more times, saving 1 tablespoon chives for later.
4. cover & bake for 45 minutes. after 45 minutes, remove the lid, and bake for about 30 minutes more, until the top is golden brown, and the potatoes are tender. sprinkle the last of the chives on top & let rest for at least 15 minutes before serving.