THIS IS FOR USE WITH THE GARLIC SHRIMP MASTER RECIPE. Heat the oil in a large, heavy saucepan over medium-high heat. Add onion, fennel and carrot. Saute 5 minutes. Add the shrimp shells and saute until the shells turn bright pink, abaout 5 minutes. Add sherry and tomatoes, and boil until almost all of the liquid evaporates, about 5 minutes. Add the water, peppercorns, thyme, parsley and bay leaf. Bring to a boil. Reduce heat and simmer for 30 minutes. Strain the stock; discard the solids. If not using right away, cool, then cover and refrigerate. Yields about 8 cups. See notes. NOTES : This recipe makes enough for both the bisque and the jambalaya. If more stock is needed, bottled clam juice can be used as an extender. Recipe by: SF Chronicle; Dec. 17, 1997 - WEEKEND COOK Posted to MC-Recipe Digest V1 #983 by Judi Moseley on Jan 4, 1998