Preheat the oven to 350 degrees Fahrenheit.

Lightly grease and flour two 8” cake pans. Set aside.

In a large bowl or stand mixer, whisk together the egg whites and cream of tartar until stiff peaks form. Set aside.

In a separate large bowl, mix together the dry ingredients: cake flour, sugar, cocoa powder, baking soda, baking powder and salt

Divide the batter evenly between the two prepared cake pans.

Bake in the preheated oven for 25-28 minutes, or until a toothpick inserted in the center comes out clean.

Allow to cool for 15 minutes, or until they have cooled enough to handle safely. Then invert the pans to remove the cakes. Set the cakes on a cooling rack to cool completely.

In a small bowl combine the two tablespoons of cornstarch with one tablespoon of water. Mix together to form a slurrry. Set aside.

Heat a large pot over medium heat. Add the butter, sugar, evaporated milk, and egg yolks. Whisk together gently. Cook, stirring constantly, until the mixture starts to boil.

Add the cornstarch slurry and simmer, whisking constantly, until frosting is thickened.

Remove from heat and stir in the vanilla extract.

Allow the frosting to cool until it is a spreadable consistency. You can speed up this process by chilling the frosting in the fridge. It may take up to two hours to cool well enough.

Use a serrated knife to trim the rounded top from one cake layer. This will help the next layer sit flat on top. Place this first cake layer on a serving plate.

Cover the top of the first cake in a thick layer of frosting.

Top with the second cake layer.

Frost the top and sides of the cake.

Sprinkle with chopped macadamia nuts.

Chill for 2 hours before slicing and serving.