Cut the Pacific saury into 2cm pieces and season with salt and pepper.

Mince the onion and garlic. Slice the black olives thinly.

Boil water in a pot, add salt (1 tbsp, not listed in ingredients), and cook the penne pasta 1 minute less than the package instructions. Drain the water.

Heat olive oil in a frying pan over medium heat. Add onion, garlic, olives, and chili flakes. Cook until the onion softens, then add the saury and cook until its color changes.

Add the tomato sauce ingredients (canned tomatoes, sugar, salt, water) and mix. Simmer over medium heat until the sauce reduces to 2/3 of its original volume.