Roasted Rosemary Potatoes with Shiitake (or Maitake), caramelized onions and Gruyere cheese
From Mimi Brodeur's forthcoming mushroom cookbook due out in September 2005

Here's one of my favorite, robust mushroom recipes made with potatoes and Shiitake (or Maitake).
These roasted potatoes remind me of the Swiss potato dish, rosti, which translates as "crunchy and golden" shredded potato pancakes. The layer of mushrooms and cheese enrich this homey potato dish.

Serves 6

Ingredients:
3 tablespoons butter
1 small sweet yellow onion, sliced thinly
1 teaspoon sugar
1/2 pound fresh Shiitake mushroom caps, cleaned and sliced (or Maitake mushrooms, cleaned and
coarsely chopped).
2 pounds russet (baking) potatoes, peeled and cut into 1/2 inch dice
1 cup shredded Gruyere cheese, about 4 ounces
1 teaspoon chopped, dried rosemary
1/2 teaspoon salt
1/4 teaspoon freshly ground black pepper

Preparation:
Preheat oven to 425ºF.
In a 10" cast iron skillet, over moderate heat, melt 1 tablespoon of the butter. Add onion and sugar. Cover and cook until onion is softened about 10 minutes. Remove cover and cook until onion slices are golden brown, about 5 minutes longer. Scrape into bowl and set aside.
In same skillet, over moderate heat, melt remaining 2 tablespoons of butter. Cook mushrooms until tender, 5-6 minutes. Scrape into bowl with onions.
In same skillet, toss potatoes with olive oil, rosemary, salt and pepper. Place skillet in the center of preheated oven and roast until potatoes are golden
brown and tender, about 35 minutes. Remove from oven, spread evenly with mushroom and onion mixture. Sprinkle with cheese and return to oven. Cook until cheese is melted about 10 minutes longer.

Time saving tip: Onion and mushrooms may be cooked a day in advance. Cover and refrigerate.