POTATO, SPINACH AND ONION GRATIN

POTATO, SPINACH AND ONION GRATIN image

Yield 8 servings

Number Of Ingredients 12

1 3/4 pounds medium-size Yukon Gold potatoes, unpeeled
2 large onions, halved, thinly sliced
1/4 cup (or more) water
2 tablespoons extra-virgin olive oil
8 ounces mushrooms, thinly sliced
1 10-ounce package frozen chopped spinach, thawed, drained
4 garlic cloves, minced
4 teaspoons chopped fresh thyme
1/4 teaspoon ground nutmeg
1 cup nonfat sour cream
1/2 cup low-fat (1%) milk
2 ounces Gruyere cheese, thinly sliced

Steps:

Cook potatoes in large saucepan of boiling salted water until just tender, about 30 minutes. Drain and cool. Cut potatoes into 1/3-inch-thick slices, removing any loose peel. Set aside. Combine onions and 1/4 cup water in large nonstick skillet. Cover and simmer over medium heat until onions are tender, stirring occasionally and adding more water by tablespoonfuls if mixture is dry, about 12 minutes. Increase heat to medium-high; add 2 tablespoons oil, then mushrooms; saute uncovered until onions are deep golden, about 10 minutes. Add spinach, garlic, thyme and nutmeg; stir 3 minutes. Remove from heat. Stir in sour cream and milk. Season with salt and pepper. Preheat oven to 350. Lightly oil 11X7X2-inch glass baking dish. Layer half of potato slices in prepared dish, overlapping slightly. Sprinkle with salt and pepper. Spread half of onion mixture over. Repeat layering with remaining potatoes, then onion mixture. Top with cheese. Bake gratin until hot, about 30 minutes. Let stand 5 minutes and serve.