Blanch ehu in 2 cups of the fish stock; remove, dice, and chill. In a sauce pot, heat margarine; saut� leeks. Add wine, sweet potatoes, limu, and the remaining 4 cups of fish stock. Bring to a boil, lower heat and simmer for 30 minutes or until sweet potatoes are soft. Add salt and white pepper. Puree soup in blender; chill. Before serving, add milk to desired consistency. Divide fish between two serving bowls; add soup. Makes 2 servings. *To make fish stock: Clean 3 lb fish heads and bones under running water. Place in sauce pot with 1 cup white wine, half cup diced onion, half cup diced leeks, half cup diced celery, 1 tablespoon whole white peppercorns, 2 sprigs fresh thyme, and 3 litre of water; cover and bring to a boil. Skim surface; simmer for 15 minutes. Strain stock through a fine sieve. Makes 2 litre . (courtesy of Tim Le, Sheraton Waikiki) Recipes compliments of Department of Business, Economic Development & Tourism and demonstrated by EXECUTIVE CHEF WILLIAM TRASK HAWAII SEAFOOD FESTIVAL JULY 1995 Reprinted with permission from: The Electric Kitchen & Hawaiian Electric Company, Inc.