This salad is typical of the delicious Venetian cooking Antonio Tommasi and Jean-Louis De Mori serve at Ca' Brea.
Roast red and yellow peppers over a gas flame or under a broiler until blackened. Place in a paper bag to cool. Peel and seed peppers, and cut into strips. Set aside until ready to use.
Poach seafood separately in simmering salted water. Cook mussels and clams until shells open, 5 to 7 minutes. Cook scallops, shrimp, and calamari until opaque, 5 to 7 minutes. Discard any unopened mussels and clams. Drain all the seafood and let cool; set aside until ready to use.
In a small bowl, whisk together oil, lemon juice, garlic, red-pepper flakes, and salt and pepper to taste.
In a large serving bowl, combine cooled seafood (keep mussels and clams in their shells), pepper strips, artichoke hearts, olives, and basil. Pour dressing over salad; mix to coat thoroughly. Serve immediately.