Seafood Cioppino

In a large pan that's at least 2 inches deep, heat the butter over medium-high heat. Add the onion , garlic, and fish and cook for 1 minute. Add the shrimp and scallops and cook, stirring occasionally and flipping the fish once, about 2 minutes more. Add the tomato, mussels, clams, and crab and pour the white wine over everything. Add the salt and pepper and sprinkle with the basil . Cover and cook until the clams and mussels start to open, about 4 minutes. (Discard any that don't open.) Remove from heat and divide the seafood and broth among 4 large shallow soup or pasta bowls. Garnish with basil sprigs and serve.