Preheat your oven to 350°F (175°C). Grease and flour the cake pans, or line the bottoms with parchment paper for easy removal.
In a bowl, whisk together the flour, baking powder, and salt. Set aside.
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy using an electric mixer.
Add the egg whites one at a time, mixing well after each addition. Then stir in the vanilla extract.
Gradually mix in the dry ingredients, alternating with the whole milk, starting and ending with the dry ingredients. Blend until just combined.
Fold in the melted white chocolate carefully until fully incorporated.
Divide the batter equally between the prepared cake pans and smooth the tops.
Bake in the preheated oven for 25-30 minutes or until a toothpick inserted into the center comes out clean. Allow the cakes to cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.
While the cakes cool, prepare the frosting. In a small saucepan over medium heat, combine the sugar, butter, evaporated milk, and egg yolks. Stir continuously until the mixture thickens and reaches a pudding-like consistency (about 10-12 minutes).
Remove from heat and stir in the vanilla extract, coconut, and pecans. Let the frosting cool until it thickens enough to spread.
Once the cakes are completely cooled, place one layer on a serving plate. Spread a generous amount of the frosting on top, then place the second layer over it.
Frost the top and sides of the cake with the remaining frosting. Slice, serve, and enjoy!