Preheat oven to 180 degrees C. Grease and flour three 20cm round baking pans. Reserve coconut juice and add enough milk to make 1 cup. Set aside.
In a small bowl sift together flour, baking powder and salt. Set aside.
In a large bowl cream copha and 125g butter until light and fluffy. Add 2 cups sugar gradually while mixing. Add 4 eggs one at a time, beating well after each addition. Add flour mixture alternately with coconut milk mixture. Add vanilla. Fold in coconut.
Divide batter evenly between pans. Bake for 30 to 35 minutes.
To Make Icing: In a saucepan combine 1 cup sugar, cream of tartar, pinch of salt and water. Bring to a boil and cook until a little of the syrup dropped into cold water forms a soft ball that holds its shape.
In a medium bowl whip egg whites at high speed until stiff but not dry. Add syrup slowly to egg whites, beating constantly. Add 1 teaspoon vanilla and incorporate.
In a large bowl, cream 2/3 cup butter well. Add egg white mixture 2 or 3 tablespoons at a time, beating well after each addition.
Spread icing between, around and on top of each layer. Sprinkle grated coconut on top of each iced layer.