For sauce, cook beef, sausage, onion, celery, carrots and garlic in a large saucepan until meat is brown. Drain any excess fat.
Add un-drained tomatoes, tomato sauce, chopped basil, salt and pepper. Bring to a low boil and then reduce heat. Simmer, covered, for about 15 minutes. Stir occasionally.
Meanwhile, cook noodles for 8 to 10 minutes so they are slightly under-cooked. Drain noodles and set aside.
For cheese filling, mix together cottage cheese, egg, Parmesan and spinach. Set aside.
Spread 1/2 cup of the sauce over the bottom of the baking dish. Layer half of the noodles in the bottom of the dish, trimming with kitchen shears as necessary to fit. Spread with half of the cheese filling. Top with half of the remaining sauce and half of the mozzarella. Repeat layers.
Place 9 X 13 dish on a baking sheet. Bake at 375 degrees for 30 to 35 minutes. Let stand for 10 minutes before serving.
I have mistakenly left out the egg in the past. It still tasted great, but never really set up in a pretty square serving. So, if the soupy plate doesn't bother you, and you have an allergy to eggs, leaving them out still works.