Put a 6 quart stock pot, heat the olive oil over medium heat. Add the scallions and fennel and cook until soft, about 4-5 minutes. Add the garlic and cook 1 minute more.
Stir in the tomato paste and cook for 2-3 minutes, until the tomato paste begins to color.
Add the white wine, broth, canned tomatoes, oregano and bring to a simmer over medium heat. Using a wooden spoon, crush the cherry tomatoes in the pot. Simmer uncovered for 25-30 minutes.
Turn the heat up to medium and bring the pot to a boil. Stir in the olives, shrimp, mussels and cod. Cook the seafood in the broth until the mussels begin to open, the shrimp begin to turn pink and the cod is flaky. Add in the broccoli rabe, ensuring it is all submerged in the broth. Cover the pot and simmer over medium low heat until the mussels are fully open, and the broccoli rabe is tender-crisp, 4-5 minutes. Stir in the parsley. Taste for seasoning and season with salt and pepper as desired.
Serve with toasted bread, friselle or garlic crostini.