Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.

In a large mixing bowl, cream together 1 cup of softened unsalted butter and 2 cups of granulated sugar until light and fluffy.

Add in the 4 large eggs one at a time, mixing well after each addition.

In another bowl, combine 3 cups of all-purpose flour, 1 tablespoon of baking powder, and 1/2 teaspoon of salt. Gradually add this dry mixture to the butter mixture, alternating with 1 cup of buttermilk and 1 teaspoon of vanilla extract. Mix until well combined.

Divide the batter evenly 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.

Let the cakes cool in the pans for 10 minutes before transferring them to wire racks to cool completely.

In a saucepan, melt 1/2 cup of unsalted butter over medium heat.

Stir in 1 cup of evaporated milk, 1 cup of packed brown sugar, and the 3 egg yolks. Cook over medium heat, stirring constantly, until thickened.

Remove from heat and stir in 1 teaspoon of vanilla extract, the sweetened shredded coconut, and chopped pecans.

Once the cakes are completely cooled, spread the coconut pecan frosting between the layers and on top of the cake.

Serve and enjoy!