Heat 40ml of the olive oil in a large frying pan on a medium heat.
Cook the seafood, starting from the largest pieces first. Add fish and large prawns first. Cook for no more than 30 seconds, tossing always. Continue with scallops, clams and calamari (or your choice of seafood mix). Cook for 30 seconds to one minute. Immediately transfer the seafood onto a plate.
Add the remaining 40 ml of oil. Add the onion and cook for approximately 5 minutes, stirring frequently. It should be soft and very aromatic.
Add the garlic and chilli and cook for a further 1 minute, stirring frequently.
Increase the heat to medium-high. Add the wine – it should be sizzling. Swirl the pan gently to deglaze the pan & lift up all the base flavours.
Add the tomato paste and the passata (or tomatoes) and the sugar.
Season well with sea salt and freshly cracked black pepper. Simmer for approximately 20 minutes. Add roughly torn basil and grated nutmeg and cook for another couple of minutes.
Whilst the marinara sauce is finishing its cooking, bring a large pot of salted water to the boil. Cook the pasta according to packet directions. If it is fresh pasta you are using, it will float to the surface after just a few minutes – indicating it is cooked. Strain but reserve one cup of the starchy pasta water.
Add the seafood to the marinara sauce.
Add the strained pasta to the marinara sauce. Loosen with ½ a cup of the pasta water and toss to combine well. Add the remaining pasta water only if it is required.
Serve in pasta bowls or on a large platter for all to help themselves to. Top with additional basil or Italian parsley.