Seafood Stock

Put all ingredients in a large pot. Add 1 quart water. Make a mental note of the water level in the pot, because you want to have at least 1 quart of stock after it has simmered for several hours. Add another 1 quart of water, enough to cover shells and vegetables by several inches. Bring to a full boil. Skim off the gray foam. Reduce the heat and simmer for at least 4 hours, adding extra water if necessary, to keep at least 1 quart liquid in the pot.

Strain the stock, discarding the shells and vegetables. If you are not using immediately, cool and refrigerate. Stock should be cooled quickly to avoid spoiling, but should not be put directly from the stove into the refrigerator. Run 2-3 inches of cold water into the sink, and add ice if you want. Pour the stock into small containers and place containers in the sink. As soon as the stock comes close to room temperature, refrigerate or freeze.