Place a large saucepan of salted water over high heat. Once boiling, add the linguine and cook until al dente. Drain, reserving 1/2 cup of the pasta cooking water (to add to the sauce later).
Meanwhile, heat a large frying pan over medium heat. Add the olive oil and heat for 1 minute. Add the onion and cook stirring for 2–4 minutes. Add the garlic and anchovies and cook, stirring for 3 minutes. Add the tomato paste, diced tomatoes, crushed tomatoes and oregano and gently simmer for about 8–10 minutes. Add the red chilli flakes (if using), capers and pitted olives, and stir through the sauce.
Add the drained linguine to the sauce, along with the reserved pasta cooking water. Gently stir the linguine through the sauce. Garnish with fresh basil or parsley.
