Heat the oil in a dutch oven over medium heat. Add the onions, celery, carrots, crushed red pepper flakes and garlic. Season with salt. Cook until vegetables are tender, about 5 minutes. Add the beef and lamb and cook on high until brown. Add the tomato paste and cook 5 minutes. Add the tomatoes and half and half and cook for 10 minutes. Add the wine, nutmeg and parmesan cheese rind, reduce the heat to low and cook for 2 hours. Season with salt.