In a covered 5- to 6-quart pan over high heat, bring broth to a boil. Reduce heat to low and simmer while cleaning shellfish.
Meanwhile, scrub clams or mussels well; pull any beards off mussels. Discard open shellfish that don't close when tapped.
Return broth to a boil over high heat. Add shellfish, cover, and cook until shells pop open, 3 to 6 minutes. Spoon shellfish and broth into bowls. Sprinkle with parsley. Serve with lemon wedges.
Creamy tarragon-shallot broth. In pan, combine 1 cup water (for clams) or clam juice (for mussels), 1 cup dry white wine, 1/2 cup chopped shallots, 1/4 cup whipping cream, and 1 teaspoon dried tarragon.
Per serving with clams: 265 cal., 34% (90 cal.) from fat; 13 g protein; 10 g fat (8 g sat.); 11 g carbo (3 g fiber); 328 mg sodium; 62 mg chol.
Garlic-ginger broth. In pan, combine 1 cup water (for clams) or fat-skimmed reduced-sodium chicken broth (for mussels), 1 cup sake or dry white wine, 1 tablespoon chopped garlic, 1 tablespoon chopped fresh ginger, and 1/4 teaspoon crushed hot chili flakes.
Per serving with clams: 154 cal., 5% (1 cal.) from fat; 12 g protein; 9 g fat (1 g sat.); 4 g carbo (2 g fiber); 56 mg sodium; 29 mg chol.
Tomato-basil broth. In pan, combine 1 can (14 1/2 oz.) diced tomatoes (including liquid), 1/2 cup water (for clams) or fat-skimmed reduced-sodium chicken broth (for mussels), 1/2 cup chopped onion, 1 tablespoon minced garlic, and 2 teaspoons dried basil.
Per serving of clams: 131 cal., 11% (14 cal.) from fat; 14 g protein; 5 g fat (2 g sat.); 17 g carbo (4 g fiber); 386 mg sodium; 29 mg chol. z