In a small pot on medium heat, melt the butter and add flour. Stir constantly until the mixture turns golden brown (about 4 minutes). Heat the milk in a separate pot until warm but not boiling. Slowly add the milk to the flour and butter and whisk constantly until mixture thickens to the consistency of gravy (or a little thicker). Add salt and grate a little fresh nutmeg or about 1/2 tsp ready grated nutmeg. Transfer to a bowl and set aside.
Assembling The Lasagna
It’s time to assemble the lasagna: In a baking dish, start by spreading a layer of tomato sauce. Add a layer of lasagna noodles, a layer of ricotta and a layer of tomato sauce. Repeat the same thing twice more. Top the last layer of noodles with sauce and leftover grated parmesan cheese.
Cook in the oven for 40 minutes.
Take the lasagna out of the oven, heat up the bechamel and pour it over the lasagna. Serve.
Preheat oven to 350 degrees F (175 C).
In a medium size pot on high heat, add olive oil, garlic, onions, celery and bell pepper. Cook for about 5 minutes, until the water’s evaporated and the veggies are starting to caramelize. Add mushrooms, lower heat to medium and cook for 3 minutes. Add wine and cook until the liquid has evaporated (about 3 minutes.) Add crushed tomatoes, fresh parsley, sugar, salt and pasta sauce, stir and bring to boil. Lower heat, cover and simmer for 20 minutes. Check on the sauce and give it a quick stir once in a while to make sure nothing is sticking to the bottom of the pot.
Meanwhile bring a large pot of salted water to boil. Cook the lasagna sheets for about 9-10 minutes. Drain and rinse in cold water.
In a bowl, mix the egg, ricotta and 1/2 cup or parmesan. Set aside.