Heat the olive oil in a large frying pan over medium-low heat. Add the chopped shallot and cook for 2–3 minutes until softened but not browned. Add the garlic, chopped anchovies, and chilli flakes. Cook gently for about 1 minute, stirring, until the anchovies begin to melt into the oil.
Add the capers and sliced olives and cook for another minute. Pour in the chopped tomatoes and add the dried oregano. Season with plenty of black pepper and a little salt, as the anchovies, olives, and capers are already quite salty.
Bring the sauce to a gentle simmer and cook uncovered for 15–20 minutes, stirring occasionally, until it has thickened and become rich and glossy.
While the sauce is cooking, bring a large saucepan of salted water to the boil. Cook the linguine according to the packet instructions until just al dente. Before draining, reserve about a mugful of the pasta cooking water for later. Drain the linguine.
Add the linguine directly to the pan with the sauce. Add a splash of the reserved pasta water and toss everything together over medium heat for 1–2 minutes. Add a little more pasta water if necessary, until the sauce is glossy and coats the pasta.
Remove from the heat and stir in most of the chopped parsley. Finish with a little extra virgin olive oil, some freshly grated Parmesan, and the remaining parsley.