Warm olive oil in large heavy bottom stock pot. Add onion, green pepper and sausage and saute until veggies are softened, about 5 minutes. Add garlic in the last minute.
Add spices and saute another 2-3 minutes, stirring frequently.
Add tomato paste and saute another 2-3 minutes, stirring frequently.
Add canned tomatoes and bring to a simmer. Cover and cook for about 10 minutes.
Add the clams, cover and simmer until all the shells open, about 7 to 10 minutes. Add additional clam broth, if necessary.
Add vinegar and tarragon and stir in.
Ladle into individual bowls and add optional seasonings, to taste.