Peruvian Fish Soup

In 6-quart saucepot, heat oil on medium until hot. Add onion and serrano; cook 8 to 10 minutes or until lightly browned and tender, stirring occasionally. Stir in garlic and cumin; cook 1 minute, stirring constantly. Stir in clam juice, tomatoes, water, potatoes, and 3/4 teaspoon salt; cover and heat to boiling on medium-high. Reduce heat to medium-low and simmer, covered, 8 to 10 minutes or until potatoes are just fork-tender. Meanwhile, cut 1 lime lengthwise in half. Cut 1 lime half in half again and remaining lime into 6 wedges to make 8 wedges in all; set aside. Add cod and remaining lime half to saucepot; cover and cook 5 minutes. Add scallops and squid; cover and cook 1 minute. Remove saucepot from heat. With tongs, remove lime half, squeezing juice into soup. Stir in chopped cilantro, and serve with reserved lime wedges. Makes about 11 1/4 cups.