For Cake
HEAT oven to 350°F. Prepare a cupcake pan with paper liners.
MICROWAVE chocolate and water in large microwaveable bowl on HIGH 1-1/2 to 2 min. or until chocolate is almost melted, stirring after 1 min. Stir until chocolate is completely melted.
BEAT egg whites in small bowl with mixer on high speed until stiff peaks form; set aside. Mix flour, baking soda and salt. Beat butter and sugar in large bowl with mixer until light and fluffy. Add egg yolks, 1 at a time, beating well after each. Blend in melted chocolate and vanilla. Add flour mixture alternately with buttermilk, beating until well blended after each addition.
ADD egg whites; stir gently until well blended. Scoop into cupcake pan lined with paper liners.
BAKE 20-25 min. or until toothpick inserted in centers comes out clean and cupcakes spring back when lightly touched. Remove and allow cupcakes to cool in pan for ten minutes, then remove from pan and transfer to a wire cooling rack. Allow to cool completely prior to frosting.
For Frosting
BEAT egg yolks, milk and vanilla in large saucepan with whisk until well blended. Add sugar and butter; cook on medium heat 12 min. or until thickened and golden brown, stirring constantly. Remove from heat.
ADD coconut and nuts; mix well. Cool to desired spreading consistency.
Calories: 389kcal | Carbohydrates: 35g | Protein: 4g | Fat: 27g | Saturated Fat: 15g | Polyunsaturated Fat: 2g | Monounsaturated Fat: 7g | Trans Fat: 1g | Cholesterol: 97mg | Sodium: 220mg | Potassium: 113mg | Fiber: 2g | Sugar: 25g | Vitamin A: 516IU | Vitamin C: 1mg | Calcium: 32mg | Iron: 2mg