2 tbs. Butter
4 tsp. Flour
1 1/4 c. Whole Milk
1/8 tsp. Pepper
Pinch of Ground Nutmeg
1 (15oz.) Container of Ricotta Cheese
1 (10oz.) Package Frozen Chopped Spinach, Thawed and Squeezed Dry
1 c. & 2 tsp. Parmesan Cheese
3 oz. Thinly Slice Proschiutto, Chopped
1 Large Egg, Beaten
3/4 tsp. Salt
1/2 tsp. Pepper
12 tbs. Olive Oil
12 Uncooked Lasagna Noodles
2 c. Marinara Sauce
1 c. Shredded Mozzarella
Preheat oven to 450º
To make the sauce: Melt the butter in a medium saucepan over medium-low heat. Add the flour and whisk for 3 minutes. Whisk in the milk. Increase the heat to medium-high. Whisk the sauce until it comes to a simmer and is thick and smooth, about 3 minutes. Whisk the pepper and nutmeg into the bechamel sauce.
Whisk the ricotta, spinach, 1 c. parmesan, prosciutto, egg, salt, and pepper in a medium bowl to blend.
Add a tablespoon or two of oil to a lrge pot of boiling salted water. Boil the noodles until just tender but still firm to the bite. Drain. Arrange the noodles in a single layer on a baking sheet to prevent them from sticking.
Butter a 13X9X2 inch glass baking dish. Pour the bechamel sauce over the bottom of the prepared dish. Lay out 4 lasagna noodles on a a work surgace, then spread about 3 tbs. of ricotta mixture evenly over each noodle. Starting at one end, roll each noodle like a jelly roll. Lay the lasagna rolls seam side down, with touching, atop the bechamel sauce in the dish. Repeat with the remaining noodles and rocotta mixture. Spoon 1 c. of the marina sauce over the lasagna rolls. Sprinkle the mozzarella cheese and remaining 2 tbs. of parmesan over the rolls. Cover tightly with foil.
Bake until heat through and the sauce bubbles, about 20 minutes. Uncover and bake until the cheese on top becomes golden, about 15 minutes longer. Let stand for 10 minutes. Meanwhile, heat the remaining marinara sauce in a small saucepan over medium heat until hot, and serve alongside.