For the batter: Preheat the oven to 350 degrees F. Line two 12-cup muffin pans with cupcake liners.
Whisk together the flour, baking soda and salt. In a mixing bowl, cream the sugar and butter until light and fluffy with an electric hand mixer. Add the eggs, one at a time, beating until each is incorporated. Beat in the vanilla. Reduce to a low speed. Add the flour mixture in 3 batches, alternating with buttermilk. Beat in the melted and cooled chocolate. Divide the batter evenly among the lined cups, filling each three-quarters full. Bake until a toothpick comes out clean, 18 to 20 minutes. Transfer to a wire rack and cool completely.
For the filling: In a large mixing bowl, combine the coconut flakes and pecans, and set aside. In a medium saucepan, combine the sugar, butter, vanilla, egg yolks and evaporated milk. Heat the pan over medium-high heat until it begins to boil. Stir constantly. Let the mixture boil for an additional 2 minutes. Remove from the heat and pour over the coconut and chopped pecans mixture. Stir until completely incorporated. Put in the refrigerator for 1 to 1 1/2 hours to cool and thicken.
For the frosting: In a mixing bowl, cream the butter and cocoa powder with an electric hand mixer on medium-high until light and creamy. Add in the vanilla. Add in the milk. Add 1 cup of the powdered sugar at a time, mixing between each addition. Add more milk as needed until you reach the desired consistency. Add the frosting to a piping bag fitted with a large star tip.
To assemble, pull out the centers of the cooled cupcake with a cupcake corer. Fill with the coconut pecan filling. Pipe the frosting onto each cupcake. Place a small amount of coconut pecan filling on top for garnish.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.