Cake:
Preheat oven to 350 degrees.
Lightly butter the bottom and sides of three 8 inch round pans.
Line pans with parchment paper.
Dust bottom and sides with flour; tap out the excess.
In a medium bowl sift flour and baking soda.
Melt white chocolate in water and cool; set aside.
At medium speed cream butter and sugar in a large bowl until light and fluffy, about 5 minutes.
Beat in one egg yolk at a time, blending well after each addition.
Beat in melted white chocolate and vanilla.
At low speed blend in sifted flour mixture alternately with the buttermilk; do not overbeat.
Fold in coconut and pecans.
Beat the egg whites until stiff peaks form.
Blend 1/3 of egg whites into cake mixture to lighten it; carefully fold in the remaining egg whites.
Spoon batter into the prepared pans.
Bake 35 - 40 minutes or until cake springs back when touched in center.
Transfer cakes in the pans to wire racks and cool 10 minutes.
Invert cakes onto the wire racks and carefully remove parchment paper; cool completely.

Frosting:
In a medium saucepan over medium heat combine evaporated milk, sugar, butter, and egg yolks.
Simmer for 10 minutes, stirring constantly.
Do not let mixture boil fast; lower the heat if necessary.
Remove from heat and stir in vanilla, pecans, and coconut.
Place the saucepan into a bowl filled with ice and stir constantly until the frosting is cool and slightly thickened.

Place a cake layer on a serving platter.
Spread 1/4 of the frosting evenly over the cake layer, making sure to spread it all the way to the edges.
Repeat with second and third layers.
Evenly frost the top and sides of the cake with remaining frosting.