Gather all the ingredients
Preparation: Thinly slice the fennel bulb. Dice the onion, bell peppers, and tomatoes. Mince the garlic cloves. Finely chop the Italian parsley. Devein the shrimp, leaving the tails on. Slice the salmon and cod. Slice the baguette roll.
Cooking the Base: In a large pot, heat 2 tablespoons of oil over medium heat. Add the diced onion and thinly sliced fennel bulb to the pot. Sauté until the onion becomes translucent and the fennel softens, about 8 minutes. Add salt and pepper. Add butter and the minced garlic, and cook for another 1-2 minutes until fragrant.
Continue cooking the base: Stir in the diced bell peppers and tomatoes. Cook for about 5 minutes until they start to soften. Add salt and pepper again. Pour in the white wine and simmer at medium heat for 8 minutes. Pour in the tomato juice, stirring in the chopped Italian parsley. Simmer for another 5 minutes on medium heat.
Adding Seafood: Add the sliced salmon and cod to the pot. Cook for about 5 minutes until they start to turn opaque. Add salt and pepper to taste. Add the large shrimp and lobster tails. Simmer for another 3 minutes, and then cover and simmer on medium heat for 15 minutes.
Prepare the Baguette Slices: While the soup is simmering, butter both sides of the baguette slices and toast them in a frying pan.
Finishing Touches: Remove the cover and stir in the finely chopped Italian parsley. Squeeze the juice of 1 lemon into the cioppino.
Serving: Serve the cioppino hot, with slices of the baguette roll on the side for dipping into the flavorful broth.