In Italy lasagna is usually made with bolognese sauce, bechamel, and parmesan cheese. It takes all day, if not longer, to make because the bolognese has to simmer for at least three hours and many Italian cooks even make their own pasta. In this lighter vegetarian version the mushroom sauce mimics the meat sauce and the bechamel is made with olive oil instead of butter. You can make the red sauce in the GSO®, the white sauce has to be done on the stove.
1 tablespoon extra-virgin olive oil, divided
1 onion, finely chopped
1 carrot, finely chopped
1 stalk celery, finely chopped
4 cups mushrooms, chopped
2 cloves garlic, finely chopped
1 28-oz can chopped Italian tomatoes
1 teaspoon dried thyme leaves
Salt and ground pepper, to taste
3 tablespoons olive oil
1/3 cup all-purpose flour
3 cups low-fat milk
1/4 teaspoon freshly grated nutmeg
12 whole wheat no-boil noodles
8 cups spinach leaves
1 cup freshly grated parmesan cheese
Set Global Sun Oven® out to preheat.
To prepare mushroom sauce: Heat 1 tablespoon oil in a large, light-weight, dark pot in GSO. Add onion, carrot, and celery. Stir to coat; cook until onion has softened, about 10 minutes. Add mushrooms and garlic; cook until the mushrooms release their liquid, 10 to 20 minutes. Stir in tomatoes, cover with a dark tea towel. Cook until sauce is thick, about 1 1/2 hours. If baking assembled lasagna on the same day leave GSO® out after removing the sauce.
To prepare white sauce: Heat the oil in a heavy saucepan over low heat. Add flour and cook, whisking constantly, until the flour starts to turn light brown, about 3 minutes. Remove from heat and gradually whisk in milk. Return pan to medium heat and cook, whisking constantly, until the sauce bubbles and thickens. Whisk in nutmeg. Season with salt to taste.
To assemble and bake lasagna: Spread 1/2 cup of the mushroom sauce in a 8- by 11-inch glass baking dish, Arrange a layer of 3 noodles on top and spread with another 1/2 cup of mushroom sauce. arrange a layer of spinach over the sauce and drizzle with 1/2 cup of the white sauce. Sprinkle 2 tablespoons parmesan over the white sauce and top with another layer of noodles. Repeat with remaining noodles. Spread remaining mushroom sauce over the top layer of noodles, sprinkle with remaining parmesan. Cover with foil. Cover with a dark tea towel and bake in GSO® until noodles are soft, about 40 minutes. Let stand 10 minutes before serving.
Lasagna can be assembled, covered and refrigerated up to 2 days before baking.