Drain the pilchards and separate them, reserving the sauce
Place the pilchards, butter, egg, herbs and garlic flakes in a food processor and blitz until combined
Form into 16 or so balls
Heat some oil in a frying pan and fry over a medium heat to seal the meatballs
Drain on paper towel, set aside and keep warm
Use the same pan and add some oil if required
Add the onion and red pepper and cook until softened
Add the harissa paste (if used) and cook for another few minutes
Stir in the sugar, tomatoes, reserved pilchard sauce and chopped coriander and cook for another 5 minutes while stirring
Cook the pasta as per the packet instructions, drain and add to the sauce, stirring to coat
Pile the pasta and meatballs in bowls top with a few meatballs and scatter with some freshly chopped parsley and a few caper berries