Preheat your oven to 350°F (175°C) and prepare two 9-inch round cake pans by greasing and lining them with parchment paper.

In a large mixing bowl, whisk together the flour, cocoa powder, baking soda, baking powder, and salt. Set aside.

In another bowl, beat together the sugar and vegetable oil until smooth. Add eggs, vanilla extract, and buttermilk, whisking until well combined.

Gradually add the dry ingredients to the wet ingredients, alternating with hot water or brewed coffee, and stir gently until just combined.

Divide the batter evenly between the prepared cake pans and smooth the tops. Bake for 25-30 minutes or until a toothpick comes out clean.

Allow the cakes to cool in the pans for 10 minutes before inverting them onto a wire rack to cool completely.

In a saucepan, combine the brown sugar, evaporated milk, butter, and egg yolks over medium heat, stirring constantly until thickened.

Remove from heat and mix in the shredded coconut, chopped pecans, and vanilla extract.

Once the cakes are cooled, place one layer on a serving plate, spread frosting between layers, and frost the top and sides as desired.