Method
Prep:1hr30min  ›  Cook:30min  ›  Ready in:2hr 

1. Remove any fat, membrane and gristle from the steak and pork. Cut the meat into thin strips lengthways, then crossways into small dice.
2. To retain all the succulence of the meat, mince it by hand. Take a large, sharp knife in each hand, and, holding them loosely, lift each up and down in turn to chop, using a rhythmic action. Lift and turn the meat with the flats of the knives and continue chopping it to a fine mince.
3. In a large bowl, mix the minced meat, anchovy, if using, breadcrumbs, egg, lemon zest and 5 tablespoons of the parsley. Season with pepper only (the anchovies will provide enough salt).
4. Use your hands to roll the meat mixture into 20 meatballs the size of large walnuts. Then place them in a dish, cover with cling film and chill for 1 hour to allow their flavour to develop.
5. To make the sauce, pour the stock and wine into a large frying pan or wok and bring to the boil, then reduce the heat to low. Add the meatballs and poach them, uncovered, for 20 minutes, turning them once or twice as they cook. Do not allow the stock to boil or the meatballs will break up. Lift out the meatballs with a slotted spoon, dry them on kitchen paper and keep them warm.
6. Put the yoghurt and flour into a small bowl, whisk until smooth, then gradually whisk the mixture into the simmering stock. Raise the heat and continue whisking until the sauce comes to the boil, then reduce the heat to low, add the capers and simmer for 3 minutes.
7. Season the sauce with pepper, pour it over the meatballs, sprinkle with the remaining parsley and serve.