Heat vegetable oil in a large pan over medium heat.
Brown the beef mince, remove with a slotted spoon, and set aside.
Brown the chicken livers in the same pan, then chop into bite-sized pieces and set aside.
Fry the onion for 5 minutes until softened.
Fry garlic, peppers, and mushrooms for 6 minutes until lightly coloured.
Add cooked mince, livers, tomato purée, and bay leaves and cook for 8 minutes.
Stir in wine and canned tomatoes, then simmer for 45 minutes.
Season to taste with salt and white pepper.
Incorporate thyme, parsley, and oregano into the sauce.
Serve sauce over cooked spaghetti and top with grated parmesan.