Preheat oven to 350°F.

Grease and flour (2) 8” round cake pans. Line bottoms of pans with parchment paper; set pans aside. (See note)

Using an electric mixer, cream together butter and sugar until light and fluffy (2-3 min. on medium speed).

Using a small mixing bowl, whisk together eggs and additional egg yolks. Add egg mixture in 2 additions, mixing fully after each addition.

Add baking powder, salt and half of the flour; stir until just combined.

Add vegetable oil, vanilla extract and milk; stir until just combined.

Add remaining flour and chocolate chips; stir until just combined. (Tip: Don’t forget to scrape the bottom and sides of the bowl.)

Pour ¼ of the batter into each of the 2 prepared cake pans. (Note: The remaining batter will be used once the first round of cakes is baked.)

Bake 20-22 minutes, or until a toothpick inserted into the center of a cake comes out clean.

Let cakes cool for 10 minutes in pan before turning them out onto a cooling rack. Repeat baking process with the remaining batter.

Using an electric mixer fitted with paddle attachment, add butter and beat on medium-high speed for 4-5 minutes, or until pale in color.

Add half of the powdered sugar; beat on low until well combined. Increase speed to medium-high and beat for 3-4 minutes. Repeat using remaining powdered sugar.

Add vanilla, salt and half of the milk; beat on low until well combined. Increase speed to medium-high and beat for 3-4 minutes. Repeat using remaining milk.

Place one layer of cake on serving platter or cake stand. (Tip: Don’t forget to remove parchment paper underneath!)

Spread ~⅓ of frosting evenly on top of cake layer.

Repeat, alternating between layers of cake and frosting. Do not frost top of cake.

Heat about 1" of water in a medium saucepan until it begins to simmer slightly. Place a small, heat-proof bowl over the saucepan. Add all of the ingredients (chocolate, butter, corn syrup and water) to the bowl, and stir occasionally until the chocolate has melted and the mixture is smooth.

Remove mixture from heat and allow it to cool at room temperature for 20 minutes before pouring over cake.

{Optional: While glaze is still wet, sprinkle top of cake with white sprinkles or jimmies.}

Let glaze cool completely before slicing cake.