I've found beef stroganoff made with lots of onions and mushrooms -- and sour cream -- so rich, and with varied tastes and textures, that I don't miss the noodles. I've also used green beans as a base -- chicken and sauce poured over them isn't spaghetti, but, again, it's a different texture that completes a meal.

I hate tomato sauces, so I don't miss those -- and can't help there, unfortunately. But cream sauces are, to me, good over anything