CALDO DE SIETE MARES - Mexican 7 seas soup
Guajillo Sauce Base:
3 garlic cloves, unpeeled
8 medium-large dried guajillo (or New Mexico) chiles, stemmed and seeded
1/2 teaspoon dried oregano (preferably Mexican)
1/8 teaspoon freshly ground pepper
Pinch of ground cumin
1 tablespoon vegetable oil or olive oil
3 quarts fish broth or chicken broth
2 large sprigs of epazote or cilantro
About 2 teaspoons salt
Sugar to taste
12 medium-large shrimp (preferably with heads)
6 small boiling potatoes, cut into 3/4-inch dice
2 cups diced zucchini or chayote
2 ears of corn, shucked, silk removed and cut crosswise into 3/4-inch rounds (optional)
1 pound tightly closed fresh mussels or clams, scrubbed (mussels' beards removed)
1 1/2 to 2 1/2 pounds boneless, skinless rockfish, bass or cod (preferably local, in season), cubed
2/3 cup finely chopped white onion, rinsed under cold water, drained
1/2 cup loosely packed chopped cilantro
1 large lime, cut into wedges
For the sauce: Roast the garlic in a heavy skillet over medium heat, turning, until it is soft and slightly blackened. Let cool, then peel. Using the same skillet, toast the chiles 1 or 2 at a time, flattening and pressing down on each with a spatula for a few seconds; flip them over and press again. Cover the toasted chiles with hot water and let steep for 30 minutes, stirring from time to time. Drain and discard water. Put the oregano, black pepper and cumin in a food processor or blender with the chiles, garlic and 1/2 cup water. Blend to a smooth puree, adding more water if necessary. Press through a medium-mesh strainer into a bowl. Heat the oil in a heavy large soup pot over medium-high heat. When hot enough to make a drop of the puree sizzle, add the puree all at once and cook, stirring, until it reduces to a thick paste, about 5 minutes. You now have a guajillo sauce base, which can be made several days in advance.
For the soup: Add the broth and epazote to the chile base and simmer over medium heat, stirring occasionally, for 45 minutes. Taste and season with salt, adding sugar to balance bitterness, if necessary. Peel and devein the shrimp, leaving the tails on. Add the potatoes to the hot broth. Simmer uncovered until the potatoes are nearly tender, about 5 minutes. Add the zucchini and cook for 3 minutes. Add the corn and mussels or clams and simmer until the shellfish open, about 2 minutes. Add the fish cubes; cook for 2 minutes. Stir in the shrimp, remove from heat, cover and let stand for 3 to 4 minutes.
Serve the soup in large warmed bowls. Pass the onion, cilantro and lime wedges at the table. Serves 6.