Brazilian Seafood Stew

1 pound mussels, scrubbed and debearded
2 tablespoons olive oil
1 onion, chopped finely
2 garlic cloves, chopped very finely
14 ounces canned chopped tomatoes
1/4 teaspoon cayenne
pinch of saffron threads
salt and pepper
2 pounds cod steaks, cut into chunks
8 ounces raw jumbo shrimp, peeled
7 ounces canned clams
3 tablespoons chopped fresh cilantro

Heat oil in a large pan of flameproof casserole over medium heat. Add onion and cook five minutes or until soft.
Stir in garlic, tomatoes, cayenned, and saffron. Season with salt and pepper. cook for five minutes, stirring occasionally.
Add the cod and mussels. Pour in just enough water to cover and bring to a boil. Reduce heat to low. Cover and simmer for 10 minutes or until the mussels open. Discard any that have not opened.
Add shrimp and clams with their juice Simmer five minutes more or until the shrimp are pink.
Stir in cilantro just before serving.