Prepare three 8-inch cake pans with parchment paper circles in the bottom and grease the sides.

In a large bowl, add all dry ingredients and whisk together.

Mix the eggs, milk, and vegetable oil into the dry ingredients until well combined.

Add vanilla to boiling water, then gradually add to the mixture and mix well.

Divide the batter evenly among the three prepared pans. Bake at 300 degrees for about 30-33 minutes or until a toothpick comes out with a few crumbs.

Remove the cakes from the oven and let them cool in the pans for about 10 minutes. Then transfer them to cooling racks to cool completely.

While cakes cool, beat the butter until smooth.

Slowly add 4 cups of powdered sugar and mix until smooth.

Add vanilla, Oreo crumbs, and salt; mix again until smooth.

Gradually add another 4-5 cups of powdered sugar until smooth. Add heavy cream as needed for desired consistency.

For the filling, measure out about 3 1/2 cups of the Oreo buttercream and mix in the chopped Oreos. Set aside.

Level the tops of the cooled cakes with a serrated knife.

Place the first layer on a cake plate. Spread half of the chopped Oreo filling on top.

Add the second layer and repeat with the remaining chopped Oreo filling.

Top with the final layer and frost the outside of the cake with the remaining Oreo buttercream. For best results, use a smooth frosting technique.

To make the chocolate ganache, place chocolate chips in a medium bowl.

Heat the heavy whipping cream just until it begins to boil, pour it over the chocolate chips, and let it sit for 2-3 minutes. Then whisk until smooth.

Drizzle ganache around the edge of the cake and pour the rest on top, spreading evenly. You can use a squeeze bottle for drizzling for better control.

After the ganache firms a little, pipe the remaining frosting around the top edge and place an Oreo between each swirl.

If desired, sprinkle a few Oreo crumbs on top and serve. This cake is best when covered for 3-4 days.