This is quite simply the best bolognese sauce I've ever tasted (and that's a lot).
Superb for lasagne or spaghetti, or simply on toast (I swear). Also freezable.
Optional extras include liver (if you puree it, it enriches the sauce) and mushrooms.
NOTE: Some measurements, such as herbs, wine and puree etc are SUBJECTIVE, don't take my measurements as gospel; experiment.
NOTE: There really is no other way to cook this without letting it simmer for several hours, I promise you it's the best way.