Melt the butter in a large heavy stockpot over medium-high heat. Add the bacon and ham and cook, stirring often, until browned, 8 to 10 minutes. Add the ground meats and increase the heat to high. Cook, stirring occasionally, until the meat is well browned, about 20 minutes.
Add the onions, carrots, celery, and mushrooms. Cook, stirring often, until the vegetables soften, about 5 minutes. Add the garlic, nutmeg, and cloves, and stir until the garlic is fragrant, about 1 minute. Stir in the tomato paste, salt, and pepper and cook for 2 minutes. Add the wine and cook until almost evaporated, about 5 minutes.
Stir in the stock and bring to a boil. Reduce the heat to medium-low. Simmer, stirring occasionally, until the sauce has thickened, 45 minutes to 1 hour.
Add the chicken livers, if using, and cook until firm, about 5 minutes. Stir in the cream and parsley. Heat through and adjust the seasoning to taste. Use hot.
Yield: about 1 1/2 quarts