Brown the beef and pork mince in a large frypan over medium-high heat. Drain excess grease. Stir in the water and black olives and season with basil, garlic powder, oregano, sage, pepper, minced garlic and onion flakes. Simmer for about 15 minutes, stirring frequently. Stir in the Napolitana sauce, and remove from the heat.
Preheat the oven to 190 degrees C.
Place a layer of the meat and sauce in the bottom of a 20x30cm baking dish. Cover with a layer of dry lasagne. Spread a thin layer of ricotta cheese over the pasta and sprinkle with a little mozzarella cheese. Cover with another layer of sauce, and repeat layering ending with the meat and sauce on top. Reserve about 1/2 cup of mozzarella cheese for later.
Bake for 45 minutes in the preheated oven, but check after 30 minutes depending on how thick the lasagne is. Lasagne is cooked when you can easily stick a knife into it. Sprinkle the reserved cheese over the top, and return to the oven for about 10 minutes for a nice melted cheese topping.