Place all A MIXTURE ingredients in a dry frying pan and cook over low heat stirring constantly, just until they begin to change color. Remove from heat. In a food processor combine the A and B MIXTURES into a smooth paste. Place 1/2 c of the coconut milk in a frying pan and heat over medium heat. Add the paste and stir untill the aroma is released, about 1 minutes. Add the remaining 1 1/2 cups of coconut milk, bring to a boil over medium heat, and boil gently for 3 minutes. Add the sugar, tamarind water, and fish soy. Simmer for 4 more munutes and use these last 3 ingredients to adjust the flavor to taste. Remove from heat. Toast the white sesame seeds and grind them roughly in a mortar. Add the peanuts and the sesame seeds to the sauce. Let the sauce cool. Place in a serving dish and sprinkle with coriander leaves before serving with satay. Serve at room temperature.