In large skillet combine tomatoes, tomato puree, tomato sauce, 1 t. salt, pepper, oregano, and onion salt. Simmer, uncovered.
Meanwhile, in second skillet sauté onion and garlic in oil until lightly brown.
Then add ground beef and rest of salt. Cook until meat loses its red color. Drain.
Add meat mixture to tomato mixture and simmer, uncovered, at least 2 hours or until thickened.
Cook lasagna noodles according to package directions. Drain and rinse with cold water.
Place several spoonfuls of sauce in bottom of 12”x8”x2” baking dish, enough to cover bottom of dish.
Top with crisscross layers of lasagna noodles, then alternate the cheeses using half of each of the ricotta or cottage cheese. Repeat layers having same amount of ingredients. End with the remaining 3 slices of mozzarella cheese on top.
Bake at 350* F for 40 to 50 minutes or until bubbly. Remove from oven and let stand 10 to 15 minutes, then cut in squares.
The tomato sauce mixture is better if cooked a long time. This sauce may be frozen ahead of time, or can be kept in the ice box for a few days. The complete dish may be made ahead of time and frozen.