Lasagna Rolls

Instructions To make cream sauce:Melt the butter in a medium, heavy saucepan over medium-low heat. Add theflour and cook for 3 minutes, whisking continuously. Whisk in the milk.Increase the heat to medium-high. Whisk the sauce until it comes to asimmer and is thick and smooth, about 3 minutes. Whisk the salt, pepperand nutmeg into the cream sauce. To make the lasagna:In a medium bowl, stir together the ricotta, spinach, 1 cup of the parmesancheese, proscuitto, egg, and 3/4 teaspoon of salt, and the pepper untilblended. Bring a very large pot of salted water to a boil over high heat. Add thelasagna noodles and cook until al dente, stirring frequently to prevent thenoodles from sticking together, Drain. Arrange the noodles in a singlelayer on a baking sheet to prevent them from sticking. Preheat oven to 450 degrees. Butter a 13x9x2-inch baking dish. Spread thecream sauce over the bottom of the prepared dish. Lay out 4 lasagna noodles on a work surface, then spread 3 tablespoons ofthe ricotta mixture evenly over each noodle. Roll the noodles up andarrange the rolls, seam sides down and not touching each other, atop thecream sauce. Repeat with the remaining noodles and ricotta mixture. Spoon 1 cup of the marinara sauce over the lasagna rolls, then sprinklewith the mozzarella and remaining 2 Tablespoons of parmesan cheese. Coverthe dish tightly with foil. Bake until the rolls are heated through andthe sauce bubbles, around 20 minutes. Uncover and bake until the cheese ontop is golden, about 15 minutes longer. Let stand for 10 minutes. Meanwhile, heat the remaining marinara sauce over medium heat until hot.Transfer to a sauceboat and serve alongside lasagna.