Soak the saltfish overnight.
Boil the fish in fresh water until tender, for about 20 minutes.
Drain it before removing bones, scales and flakes.
Heat oil in a large pan. Add peppers, spring onions, onion and garlic. Cover and cook over low heat for 5 minutes, stirring occasionally.
Add the tomatoes and simmer over medium heat for 2 to 3 minutes.
Add saltfish, butter, salt and pepper. Cover the stew and simmer over low heat for 5 minutes.