For the Bouillabaisse: Place the stock on the heat and bring to a simmer. Add the saffron, leeks, tomatoes, orange juice, orange zest, fennel, garlic, and parsley. Season with salt and pepper. Add the fish and lobsters. Cook for 8 minutes. Add the shrimp, mussels, and clams. Cook for 6 minutes, or until the shells have opened. Discard any shells that do not open. Season with salt and pepper.

To assemble: Remove the seafood from the pan and place on a large platter. Pour the stock into a serving bowl. Serve the Rouille and crusty bread on the side of the Bouillabaisse. For individual servings, arrange the seafood in a shallow dish. Ladle the stock over the seafood.