- 2 tablespoons olive oil
- 1 small onion, chopped coarse
- 1 small bulb fennel, or the stalks of the fennel, chopped coarse
- 1 small carrot, chopped coarse
- 4 quarts shrimp heads and/or shells
- 3 quarts water or chicken broth
- 3 sprigs fresh thyme (optional)
- Heat the oil in a heavy-bottomed pot large enough to hold the soup and add the chopped vegetables. Cook over medium heat until softened but not browned, about 10 minutes. Add the shrimp heads and shells and turn the heat to high. Continue cooking over high heat while stirring around the heads and shells until the mixture smells fragrant and everything turns red, about 4 minutes.
- Let cool a few minutes and transfer the mixture to a food processor. Chop for about 30 seconds—enough to break the heads and shells up without turning them into a purée. Put the processed mixture in a pot and add the water or broth and the thyme, if using. Bring to a gentle simmer and simmer for 1 hour—don’t let the broth come to a full boil—and skim off any froth and scum that floats to the top of the pot. Strain the broth and reserve the shells and heads for shrimp butter or creamy shrimp broth.
- CREAMY SHRIMP BROTH:
- This broth uses cream to extract the flavor and color from shrimp shells and heads. Prepare the Fat-free Shrimp Broth as directed, but substitute 3 cups heavy cream for 1 quart of the broth or water.