Prepare 1 box of yellow cake mix according to instructions on box.
Add chocolate chips to the cake batter.
Grease two 8-inch (20 cm) cake pans, and pour batter into each pan. Bake according to box instructions.
Remove cake from pans and let cool.
Prepare for the cookie dough by evenly spreading flour out on a baking tray and baking for 5 minutes. This will cook out any potential bacteria in the raw flour.
In a large bowl, mix flour, sugar, butter, vanilla, milk, chocolate chips, and salt until combined evenly. If flour is clumpy after baking, use a siever to help get out the clumps.
Take a cake pan and line it with plastic wrap. Then fill the pan with half of the cookie dough mixture.
Take the other half of the cookie dough mixture, and roll it into small balls to be used as a garnish.
Refrigerate cookie dough layer and dough balls for 30 minutes.
In a large bowl, mix butter, powdered sugar, heavy cream, vanilla extract, and salt with hand mixer.
Use a serrated knife to cut the round top off of the cake so the cakes are even and flat. Spread a light layer of buttercream at the center of the cake stand.
Place the first cake on a cake stand, and spread a light layer of buttercream at the center.
Remove cookie dough layer from the pan using the plastic wrap, and place layer on top of the cake. Spread a light layer of buttercream at the center of the cookie dough layer.
Place second cake on top. Shave down the edges of the cake if necessary so that each layer evenly fits over the other. Add the remaining amount of buttercream to the top layer of cake, and frost the cake completely.