Rinse the fish frames well. Heat the olive oil in a large stockpot over medium heat. Add the fish frames and sweat over medium heat, stirring often, until the frames give off liquid, about 10 minutes. Add the remaining ingredients and heat to the boil. Reduce the heat and simmer uncovered 30 minutes, skimming the scum from the surface often. Strain through a cheesecloth-lined strainer. Let cool to room temperature, then refrigerate or freeze.
For shellfish stock, use the shells of 6 large lobsters, chopped as fine as possible, or the shells from
© 1998 Joyce Goldstein. All rights reserved.