Slightly bitter Swiss chard (which is a variety of beet) was reportedly named for the Swiss botanist who identified the green. In this dish, chard's earthy flavor balances out the rich, creamy béchamel sauce.
Ingredients
2 1/2 cups whole milk
1 Turkish bay leaf
6 tablespoons (3/4 stick) unsalted butter
1/4 cup all purpose flour
1/2 teaspoon coarse kosher salt
1/2 teaspoon (scant) ground nutmeg
Pinch of ground cloves
1 pound Swiss chard, center rib and stem cut from each leaf
Test-kitchen tip: To test for doneness, insert the blade of a small knife deep into the center of the lasagna for 30 seconds. remove the knife and feel the blade. If it's hot, so is the lasagna.
Directions
Bring milk and bay leaf to simmer in medium saucepan; remove from heat. Melt butter in heavy large saucepan over medium-low heat. Add flour and whisk to blend. Cook 2 minutes, whisking almost constantly (do not let roux brown). Gradually whisk milk with bay leaf into roux. Add 1/2 teaspoon coarse salt, nutmeg, and cloves and bring to simmer. Cook until sauce thickens enough to coat spoon, whisking often, about 3 minutes. Remove bay leaf. DO AHEAD: Béchamel sauce can be made 1 day ahead. Press plastic wrap directly onto surface and chill. Remove plastic and rewarm sauce before using, whisking to smooth.
Blanch chard in large pot of boiling salted water 1 minute. Drain, pressing out all water, then chop coarsely. Heat 2 tablespoons oil in heavy medium skillet over medium-high heat. Add onion, half of garlic, and crushed red pepper. Sauté until onion is tender, 3 to 4 minutes. Mix in chard and season to taste with coarse salt and freshly ground black pepper.
Heat remaining 2 tablespoons oil in heavy large nonstick skillet over medium- high heat. Add mushrooms and remaining garlic. Sauté until mushrooms are brown and tender, 7 to 8 minutes. Mix in nutmeg and season with coarse salt and pepper.
Cook noodles in medium pot of boiling salted water until just tender but still firm to bite, stirring occasionally. Drain; arrange noodles in single layer on sheet of plastic wrap.
Brush 13 x 9 x 2-inch glass baking dish with oil to coat. Spread 3 tablespoons béchamel sauce thinly over bottom of dish. Arrange 3 noodles in dish to cover bottom (2 side by side lengthwise, then 1 crosswise). Spread half of chard mixture over pasta, then half of mushrooms. Drop half of ricotta over in dollops and spread in even layer. Sprinkle with half of Fontina, then 4 tablespoons Parmesan; spread 3/4 cup béchamel over. Repeat layering with 3 noodles, remaining chard, mushrooms, ricotta, Fontina, Parmesan, and 3/4 cup béchamel. Cover with 3 noodles and remaining béchamel. DO AHEAD: Can be made 2 hours ahead. Cover with foil. Let stand at room temperature.
Preheat oven to 400°F. Bake lasagna covered 30 minutes. Uncover and bake until heated through and top is golden brown, 20 to 30 minutes longer. Let stand 15 minutes before serving.
