Pour the olive oil into a large skillet and set over medium-low heat. Add the anchovy fillets and stir continuously for 2 to 3 minutes until they completely dissolve into the oil, leaving no visible pieces.

Add the sliced garlic and red pepper flakes. Cook for 1 to 2 minutes, stirring, until the garlic is pale and fragrant but not colored.

Add the hand-crushed tomatoes and all their juices. Stir to combine, raise heat to medium, and bring to a gentle simmer.

Simmer uncovered for 15 minutes, stirring occasionally, until the sauce reduces slightly and the oil separates at the edges.

Add the olives and capers. Stir, reduce heat to medium-low, and simmer for a further 8 to 10 minutes until the sauce is thick and the tomatoes have broken down fully.

Bring a large pot of water to a rolling boil. Add 40 g of salt, then the spaghetti. Cook according to package instructions until al dente, usually 8 to 9 minutes.

Reserve 120 ml of pasta cooking water before draining. Drain the spaghetti through a colander.

Transfer the drained spaghetti directly into the sauce pan. Toss over medium heat for 60 to 90 seconds, adding a splash of pasta water if needed to loosen the sauce and help it cling.

Plate immediately. Drizzle with a little raw olive oil and scatter chopped parsley over the top if using. Serve without cheese.