To the same casserole, add the garlic and reduce heat to medium. Cook garlic 1 to 2 minutes, until it is softened but not browned. Add the tomatoes, tomato paste, rosemary and wine and simmer 5 minutes.
Return the rabbit to the casserole, cover loosely and cook over low heat for 1 hour, until meat is very tender. In a small bowl, combine the liver and the vinegar and mash well with a fork. Add the liver mixture to the casserole and cook 10 minutes. Add the basil leaves, remove from heat and serve immediately.