In a large pan, heat 4 tablespoons of olive oil and fry up the crushed garlic and anchovy fillets.
Remove the garlic and add the chopped tuna belly. Cook a few minutes and add the chopped tomatoes, chilli and, after adjusting the salt, continue to cook for another 10 minutes.
Boil the macaroni in salted water, drain when al dente and toss with the sauce. Decorate with parsley and serve.