In a large dutch oven heat the olive oil over medium heat. Add the onion, celery and carrot and cook, stirring occasionally until tender, about 8 minutes. Add the chicken livers and sage. Season with pepper and cook, stirring until the livers are no longer red, about 3 minutes.

In batches, add the ground meat, letting it brown before adding the next batch. Continue cooking until no pink remains.

Drain off most of the fat and then add the red wine. Bring the mixture up to a boil, stirring to break up the meat and cook until almost all of the wine is gone, about 10 - 15 minutes. Add the stock, tomatoes and basil. Bring to a boil, reduce to a gentle simmer (an occasional bubble). Cook, uncovered until the sauce is thick, dark and rich, for at least 1 hour - preferably longer. Stir in the cream, if using and simmer for another 10 minutes or so to heat it through or longer if you prefer. Season to taste with salt and pepper.

You can make the sauce up to 2 days in advance and refrigerate. The sauce also freezes beautifully. If freezing, let the sauce cool (put in a metal bowl set into another bowl filled with ice water) before freezing.