In a large, heavy based stockpot heat half of the olive oil. Add the beef and cook until browned all over. Transfer to a plate and set aside.
Heat the remaining olive oil over medium heat. Add the onion and cook for 2 minutes, then stir in the carrot and celery for 5 minutes or until the onion is soft. Stir in the bay leaves, thyme, tomato paste and peppercorns. Cook for 2 minutes, then return the beef to the pan.
Pour the cold water over the beef and vegetables. Cover and bring to the boil, then reduce heat to low and simmer for 2 hours. Stir the brodo di carne (beef soup) occasionally, skimming any scum that rises to the surface. Take the stockpot off the heat.
To make the mini meatballs: Place the bread slices in a medium-sized bowl and pour the milk over to soak for a few minutes. Add the veal mince, egg yolk and Parmigiano Reggiano to the mince mixture. Season well with salt and pepper.
Use clean hands (or you may wish to use disposable gloves) to break up the bread evenly and mix until just combined. Using wet hands, roll a teaspoon of meat mixture into a meatball. Transfer meatball to a plate and repeat with the remaining meat mixture. The meatball mixture will be soft however firm up once refrigerated. Cover the meatballs with plastic wrap and refrigerate for a minimum of 20 minutes before cooking.
Remove the onion, carrots, celery and potato. Strain the beef soup through a fine sieve into a clean saucepan, using the back of the ladle to extract as much flavour as possible. Season with salt to taste.
Note: The vegetables can be served on the side or are perfect to make a pie the following day.
Place the saucepan with strained ‘brodo di carne’ (beef soup) back onto medium heat. Bring to the boil. Carefully drop meatballs, one at a time, into the brodo di carne and stir gently. Simmer for 15 minutes or until meatballs are cooked through. Add the Anelli pasta, referring to the cooking time specified in pasta packet instructions.
To serve, spoon the meatballs among serving bowls and ladle hot brodo di carne with Anelli pasta over the meatballs. Top with Parmigiano Reggiano – buon appetito.