Put a big pot of salted water to boil. This is for your pasta.
In a hot pan, on high heat, add some olive oil, garlic and the anciovies
Then add the octopus. Sear the octopus on both sides. 1-2 minutes each side. Then add the chopped olives
Add the passata di pomodoro - you can use fresh tomatoes as well, but as the octopus is cooked, i generally dont like to let the sauce cook too much
Add salt and pepper
lower the heat, cover and simmer for 5 minutes. Taste it now for seasoning. If you need to add more, now it is the time
Cook the pasta in the boiling water.
When the pasta is aldente, transfer to the saucepan. Reserve some cooking water. It is filled with starch which will help everything get together in the end
Mix everything, top with a bit of pasta water and olive oil. Depending on how you like your pasta
Done