Note: This makes a couple of casserole dish sizes. It is such a time consuming dish, that we find that making multiples and putting some in the freezer (prior to baking) is the most reasonable use of this effort
In a large skillet, cook buffalo and sausage (removed from casings) over medium heat until no longer pink. Add the tomato sauce, tomato paste, stewed tomatoes, garlic, sugar and seasonings. Bring to a boil. Reduce heat. Simmer, uncovered, for one hour, stirring occasionally.
In a large bowl, combine the eggs and parsley. Stir in the cottage cheese, ricotta and Parmesan cheese.
When meat sauce is ready, get a baking dish ready. This can be put into one large dish, or broken up into smaller dishes. Spread a thin layer of the meat sauce in the bottom of the dish. Add one layer of noodles, then ladle meat sauce over the noodles. Apply a layer of cheese mix, topped with mozzarella. Add a layer of the optional mushrooms if desired. Repeat another layering of noodles, meat sauce, cheese sauce and mozzarella. Then top off with a layer of noodles, a thin layer of meat sauce and any remaining mozzarella spread evenly.
Cover and bake at 375 degrees for 50 minutes. Uncover and bake for 20 minutes longer or until heated through. Let stand for 15 minutes before cutting.