combine seasoning mix in small bowl. melt the butter in a 4 quart pot. soon as butter add serranos, garlic, mushrooms, lemon grass and seasoning mix. cook, stirring frequently. when mixture begins to stick about 2 minutes. add fruit juices and fish sauce. cook 5 minutes over high heat, until liquid barely covers the bottom of the pan. add stock. cover and bring to full boil. add shrimp and parsley . return to full rolling boil. remove from heat and serve instantly.