Cook meat and onion over medium heat until browned. Stir in spaghetti sauce, basil and salt.
In a bowl, mix the cheeses well with the optional eggs.
Start layering in a buttered crock pot: Meat mixture, a layer of noodles, cheese mixture, optional veggies. Keep going with 3-4 layers, making sure that the noodles are always near some sauce. (OR if you're not using lasagna noodles, just stir it all together, but make sure all noodles are under the surface with some sauce/liquid on top.)
Cover and cook on low heat for 6-8 hours or high heat for 2-4 hours until noodles are tender.
Sprinkle the top of the lasagna with the mozzarella cheese and more parmesan if you love it like we do. Cover while the cheese melts and then it’s ready to serve.