Prepare seafood stock. You'll need the shells from the lobster and shrimp for this, reserving the shrimp and lobster meat for later. Bring a large pot of salted water to a boil and prepare an ice bath. Add lobster tails to boiling salted water and cook for 4 minutes. Remove lobster with tongs to ice bath, keep water in the pot simmering on stove. On cutting board, snip down lobster backs with kitchen shears and devein as you would shrimp. Remove shells to a bowl, do not discard. Cut lobster meat into large chunks and refrigerate. Peel and devein shrimp, saving shells in bowl with lobster shells. Refrigerate shrimp.
To the boiling lobster water add lobster shells and shrimp shells, chopped carrots, chopped celery, ½ cup diced onion, 2 bay leaves, parsley sprigs and peppercorns. Cover and simmer for 2 - 3 hours, stirring occasionally until a nice, rich stock has developed. Strain stock and reserve, you want at least 4 cups.
In a large Dutch oven, heat 2 tablespoons olive oil and 2 tablespoons butter over medium heat. Add the 2 chopped onions, garlic, red pepper, celery and chopped parsley. Sprinkle with salt and sauté until softened, about 5 or 6 minutes.
Add the bay leaves, basil, oregano, thyme, crushed red pepper, salt and tomato paste. Stir to combine well and fragrant. Add the wine and boil and stir for about 4 - 5 minutes until reduced by half.
Add 4 cups of the reserved seafood stock and the hand-crushed tomatoes and their juices to the pot. Stir and bring to a boil and then simmer for 30 minutes to one hour to develop the broth. (If you didn't make the seafood stock, this is where you could add 2 bottles of clam juice instead.) This stock/broth can be made ahead of time and refrigerated for up to 2 days.
Add the clams, discarding any that are open. Cover and cook at a steady simmer for 5 minutes.
Meanwhile, heat a large skillet over medium heat and drizzle with olive oil. Dry cod and scallops and sprinkle with salt and pepper. Add the cod and scallops to the pan and sear cod for 5 minutes undisturbed. Carefully flip cod and scallops and add a few ladles of broth mixture to the pan to finish cooking.
Back to the pot with the clams, carefully stir in the mussels, lobster meat and shrimp. Cover and simmer for about 5 - 7 minutes until just cooked through and clams and mussels have opened (discard any unopened clams or mussels). Remove bay leaves and taste for salt.
In shallow bowls, place a portion of cod and scallops and ladle the seafood stew over the top. Sprinkle with some chopped parsley and serve immediately with warm crusty sourdough bread. Enjoy!