In a large bowl, beat the softened butter until creamy.

Add the granulated sugar and brown sugar and beat until well combined.

Beat in the milk and vanilla extract.

In a separate bowl, whisk together the heat-treated flour and salt. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Fold in the chocolate chips.

Refrigerate the cookie dough frosting for at least 30 minutes.

Preheat oven to 350°F (175°C). Grease and flour two 8-inch round cake pans.

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

In a separate bowl, whisk together the vegetable oil, buttermilk, egg, and vanilla extract.

Add the wet ingredients to the dry ingredients and mix until just combined. Be careful not to overmix.

Gradually stir in the hot water. The batter will be thin.

Pour the batter evenly into the prepared cake pans.

Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean.

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

Once the cake layers are completely cooled, place one layer on a serving plate.

Spread a generous amount of the chilled cookie dough frosting over the first cake layer.

Carefully place the second cake layer on top.

Frost the top and sides of the cake with the remaining cookie dough frosting.

Optionally, decorate with extra chocolate chips.

Slice and serve.