Step 1 Heat the oil in a stockpot over medium heat. Add the onion, peppers, leek and garlic and cook, stirring occasionally, until the onion is golden, about 10 to 15 minutes.
Step 2 Add the tomato paste, fresh and canned tomatoes, wine, parsley, oregano, marjoram, basil and dried chiles. Cook 5 minutes. Add the clam juice and bring to a boil. Reduce the heat. Simmer, covered, 15 minutes.
Step 3Add the fish, mussels, calamari, clams and crabs. Simmer 10 minutes, removing the clams and mussels as they open and the fish as it is cooked through. Discard any unopened shellfish. Divide the seafood among serving bowls and ladle the broth over. Serve hot.