In a medium-size pot, add all Pomodoro sauce ingredients (2 lbs. Roma tomatoes, ½ cup olive oil, ½ large onion, 4 cloves garlic, 3 Tbsps. fresh basil, and 3 Tbsps. fresh oregano) Cover and let simmer for about 30 minutes. Stir often.
When cooked for 30 minutes, divide the sauce in half. Keeping one half set in a bowl and aside for later. With the other half, blend with an immersion blender or stand up blender until smooth and set aside for later.
Cream Meat Mixture
In a medium-size pot, add 2 Tbsps. olive oil, chopped ½ large onion, minced 2 cloves garlic, and 1 medium carrot. Saute over medium to high heat for 10 minutes. Make sure you don't burn the garlic.
Add ½ cup white wine to the softened and sauteed vegetable mixture and cook on medium heat for another about 15 minutes, burning off alcohol.
Brown the 1 lb. ground beef in a large skillet thoroughly. Drain grease and return to skillet.
Add ½ cup heavy cream, sauteed vegetable mixture, and the unblended Pomodoro sauce which was set aside earlier. Return to low-medium heat and simmer for 30 minutes.
Bechamel Sauce
In a separate saucepot, melt ¼ stick butter on medium heat. Whisk in 3 Tbsp. all purpose flour until a thick paste mixture is made.
Slowly whisk in 1 cup milk and 1 cup heavy cream, then cook until sauce thickens. Add ¼ tsp. nutmeg and salt and pepper to taste. Keep warm until ready to use.
Assembly & Bake
Boil the 12 whole lasagna noodles if you have not done so. Boil them so they are underdone. They will be easier to handle and put in a baking dish.
Preheat the oven to 375 °F and take out a 13x9 deep baking casserole dish or specific lasagna pan.
1. Coat the bottom of the pan in a thin layer of blended Pomodoro sauce.2. Lay down 3 cooked noodles.3. Coat noodles with a thin layer of blended Pomodoro sauce.4. Sprinkle some meat mixture on top of Pomodoro sauce.5. Drizzle some Bechamel sauce over meat.6. Sprinkle on part of the 16 oz mozzarella cheese.7. Lay down 3 cooked noodles. And repeat starting with step 3.
Finish the top layer with the remaining Pomodoro sauce and mozzarella cheese.
Cover lasagna with foil and bake for 1 hour.
After an hour, uncover and broil the top mozzarella cheese to brown just slightly.
Take the lasagna out of the oven and let it cool for 15 minutes before serving, so it won't fall apart when you cut into it.