Add the celery and carrots and cook for about 2 minutes, then add the ground chuck, season with salt and pepper, and cook, breaking up the meat, until just cooked through. Add the whole milk and simmer until completely evaporated, then stir in freshly grated nutmeg, followed by white wine.
Stir in salt and nutmeg and remove the pot from the heat. Let it cool for 15 minutes, then stir in the ricotta cheese, seasoning with more salt if needed. Boil the lasagna noodles in a large pot of heavily salted water to just under al dente. As the lasagna cooks, preheat your oven to 375°F and brush a 9×13-inch pan with olive oil. Preheat the oven to 375 degrees F. Ladle a small amount of ragu in a 9x13 inch baking dish and spread it out to cover, then top with a sprinkling of grated parmesan cheese. Assemble the lasagna by layering sheets of pasta, then a thin layer of béchamel sauce, then a thin layer of ragu and a sprinkle of parmesan cheese. Lower the heat to medium-high heat and cover with a lid. Cook for 10mins. In the meantime, prepare the bechamel sauce: Melt the butter in a sauce pan on medium heat. Once fully melted, add the flour and whisk together until you get a smooth batter. Fry for a minute or two and then start gradually adding the milk. 1 hour 20 minutes (20 minutes active) no-boil 6½-by-3½-inch lasagna noodles (see note) extra-virgin olive. Heat the oven to 350°F with a rack in the middle position. Place the noodles in a 9-by-13-inch baking dish, then add hot water (about 140°F) to cover, along with the oil and 1½ teaspoons salt; swish the noodles around to dissolve the