This dish blew me away. It's a keeper and my new go-to potato dish. I kept going back for more and more. The depth of flavors was incredible. It's a classic and simple pairing of leeks and mushrooms tucked between thin-layered potatoes and cheese.
It's important to use a mixture of mushrooms for this recipe. I used a pre-packaged blend I bought from the grocery store that included crimini, shitake, and oyster mushrooms. They have a woodsy flavor you can't get from white button mushrooms alone. And don't sub onion for the leeks.
- 2 cups mixed, chopped mushrooms
- 1 cup chopped leeks
- 1 small garlic clove, pressed or finely minced
- 1.5 pounds potatoes
- 3/4 cup cheese (I used half white cheddar and Parmesan)
- 1 cup heavy cream
- Kosher salt and pepper to taste
Cut off root ends of leek and slice off to area that is just beginning to turn green (see picture above). Slice in half lengthwise. Peel apart and check for sand and grit. Wash if necessary. Pat dry and chop.
Add about 2-3 teaspoons olive oil to a pan and sautee leeks just until they begin to brown. Remove to a plate and set aside.
Add a bit more olive oil to pan and add mushrooms. Cook just until they begin to give up their juices, 5-7 minutes. Add leeks to pan. Stir. Add garlic and stir just until fragrant, about one minute. Remove from heat. Salt and pepper and to taste.
Microwave cream just until warm, about 1 minute. Set aside.
Peel and slice potatoes into 1/8-inch rounds using a mandolin. Save largest rounds to be placed on top last.
Butter or spray an 8 x 8 inch baking dish. Gently layer half of the potatoes into dish in overlapping rows, like shingles. Do one row horizontal, the other vertical. Give a slight sprinkle of Kosher salt and pepper. Spoon mushroom and leek mixture over potatoes. Sprinkle with half the cheese and then layer rest of potatoes on top, ending up with largest slices. Drizzle in the cream being sure to coat top layer of potatoes. Cream will not rise to cover the entire dish. Top with remaining cheese.
Cover tightly with aluminum foil. Bake in a 400 F. degree oven for 35 minutes. Uncover and continue to bake uncovered for another 30 minutes or so until potatoes are tender and top is golden. Remove from oven and allow to sit for at least 20 minutes to allow potatoes to re-absorb juices. Cut and serve with a dollop of sour cream, if desired.