Scalloped Potatoes with Wild Mushrooms

From “Here in America’s Test Kitchen”

This recipe takes some time, but it’s sooooo worth it! I’m too late for Passover on this one, but just in time for Easter.

Ingredients

1/2 ounce dried porcini mushroom pieces

2 T unsalted butter

1 small onion, minced

3 1/2 ounces fresh shiitake mushrooms, sliced º-inch thick

5 ounces fresh cremini mushrooms, sliced º-inch thick

2 medium garlic cloves, minced (about 2 t)

3 cups heavy cream

1 cup whole milk

4 sprigs fresh thyme

2 bay leaves

2 teaspoons salt

1/2 teaspoon ground black pepper

4 pounds russet potatoes, peeled and cut into 1/8-inch-slices

1 cup shredded Gruyere (about 4 ounces)

Directions

1. Cover dried porcini pieces with 1/2 cup hot tap water in small microwave-safe bowl. Cover with plastic wrap. Cut several steam vents with paring knife and microwave on high power for 30 seconds. Let stand until mushrooms soften, about 5 minutes. Lift mushrooms from liquid with fork and mince, using chef’s knife (you should have about 2 tablespoons.) Pour soaking liquid through a strainer lined with paper towel and reserve.

2. Heat oven to 350 degrees. Meanwhile, melt butter in large Dutch oven over medium-high heat until foaming subsides, about 1 minute. Add onion, fresh shiitake, and fresh cremini and saute until the mushrooms release their moisture, about 2 minutes. Add minced, rehydrated porcini along with their liquid and cook until all mushrooms are tender and liquid has reduced to about 2 tablespoons, about 3 minutes. Add garlic and sautÈ until fragrant, about 30 seconds. Add cream, milk, thyme, bay leaves, salt, pepper, and potatoes and bring to simmer. Cover, adjusting heat as necessary to maintain light simmer, and cook until potatoes are almost tender (paring knife can be slipped into and out of center of potato slice with some resistance), about 15 minutes.

3. Remove and discard thyme sprigs and bay leaves. Transfer potato mixture to 3-quart gratin dish and sprinkle with cheese. Bake until cream has thickened and is bubbling around sides and top is golden brown, about 20 minutes. Cool for 5 minutes before serving.

NOTE: Make sure you have 4 pounds of potatoes because there’s a lot of sauce! I think I may have used too few potatoes when I made this, but it was still delicious.