Preparation

• Meat sauce:
  In a large heavy saucepan heat oil over moderate heat. Add onion, parsley and garlic.
  Cook until onions are soft, about 5 minutes. Add beef and cook while stirring and breaking up the meat, until evenly brown.
  Add tomatoes, beef stock, tomato paste, oregano and bay leaves; cook stirring over medium heat until mixture starts to simmer.
  Reduce heat and simmer for one hour or until thickened to desired consistency.
  Remove bay leaves. Add salt and pepper to taste.
  
  PASTA:
  Cook 1 pound of lasagna in a large pot of salted boiling water until al dente. Transfer to cold water to cool the pasta.
  When cold, arrange pasta on a sheet pan.
  Cover with a moist towel.
  TO ASSEMBLE LASAGNA:
  Spread about 1/2 cup of meat sauce over the bottom of a 13 by 9 inch deep baking dish. Arrange a layer of lasagna noodles on top. Spread with a little meat sauce, then a little cream sauce, and half of the spinach. Sprinkle with mozzarella cheese.
  Repeat the same process until all ingredients have been used, finishing with cream sauce and cheese.
  Bake at 400 degrees for 20 to 30 minutes, or refrigerate until needed, then bake at 375 degrees for 40 to 50 minutes.