Preheat the oven to 200°C. In a mixing bowl, combine the panko breadcrumbs and Parmesan. Line a baking tray with baking paper, then spread the crumb mixture into a large, even disc. Bake for 10 minutes, or until golden brown. Set aside to cool and harden.
Squeeze the pork sausage meat out of the casings and place into a mixing bowl, discarding the casings. Add the pork mince and gently mix to combine. Form the mixture into evenly sized meatballs, taking care not to overwork it to keep the meatballs tender. Heat a large frying pan over medium-high heat and add 2 tablespoons of the olive oil. Brown the meatballs on all sides, working in batches if necessary, then set aside. Heat the remaining oil in a large pot over medium heat. Add the onion and celery, and cook until the onions begin to caramelise. Stir in the garlic, red chilli flakes, and Italian herbs, and cook for an additional 1-2 minutes. Pour in the tomato purée and chopped tomatoes, and cook for 5 minutes to reduce slightly. Add the chicken stock and bring to a simmer. Stir in the pasta and cook according to the package instructions. When the pasta is nearly done (about 2 minutes remaining), pour in the cream and simmer gently. Stir in the chopped oregano and season well with salt and pepper.
Ladle the soup into bowls, top with the browned meatballs and garnish with fresh basil and shards of the panko-parmesan crisp. Add a light grating of fresh Parmesan if preferred.
