Heat a spoonful of olive oil in a pot (preferably terracotta), add the chopped onion and garlic and cook for a few minutes, turning frequently. Add the minced beef, stir well, then add the carrot and celery left whole, the wine and the spices. After cooking them for 10 minutes, add plenty of vegetable stock and seasoning. Cover the pot and simmer for one and a half hours over medium heat, adding stock if necessary. In the meantime wash and prepare the spinach, drain, and cook in a covered pan without adding water. Drain thoroughly, chop up and set aside. When the meat sauce is cooked, add the spinach, mix well and then cook for about another half hour, adding stock if necessary to keep the sauce moist.
In the meantime prepare the maltagliati. Put the flour in a mound on a clean work surface. Make a well in the centre, break the eggs into it and add a pinch of salt. Work in the flour with your fingertips for 15 minutes until a relatively firm dough is obtained. Use a rolling pin to roll out the dough to a thin sheet; cut into irregular lozenge shapes.
Bring a large pan of lightly salted water to the boil and put in the maltagliati; as soon as they are cooked, drain well and place in a hot dish with melted butter and the meat and spinach sauce.