Preheat oven to 350°F. Line three 8-inch cake pans with parchment or silicone rounds, and /or grease with non-stick or baker’s floured cooking spray.

Mix chunks of room-temperature butter slowly into the dry mix, on a low speed. Continue to mix until no large chunks of butter remain, and the mixture becomes crumbly.

Divide batter evenly between the prepared cake pans (I find a kitchen scale helpful for this part). This guarantees your layers will bake to be the same height.

Bake for 35-37 minutes (or until a toothpick comes out clean). Allow cake layers to cool for 10-15 minutes on a wire cooling rack before removing from pans – it helps to run an offset spatula or knife around the perimeter of the pan first. Cool completely before frosting. Set in the fridge or freezer to accelerate the cooling process if desired.

Beat together softened cream cheese and butter; slowly add in powdered sugar alternating with milk until frosting reaches desired consistency. Add vanilla and salt and beat until well combined.

Remove about 1 cup of frosting for filling, then beat in frosting whitener.

Combine reserved 1 cup of frosting and crushed Oreos; stir until well blended.

Place a smear of frosting on your cake circle (to keep the cake from sliding while you decorate it) and center your first cake layer in the center of the circle.

Pipe a small ‘dam’ of frosting around the outer edge to contain your filling so it doesn’t show through to the outside of the cake.

Add filling to center of cake layer and smooth to the edges. Add your next cake layer on top, and repeat the process with your remaining cake layers.

Basically you’re just spreading a layer of frosting over the outside of the cake, to keep crumbs out of your final layer.

Cut about a 6-inch band section and cut the end to a point to make the end of the collar.

With a knife or small cookie cutter, cut out a black rectangle the same height as the collar (I used the same ruler as a guide). Cut out the center to make the buckle, and use a couple dabs of water to adhere to the cake.

Shape the ‘spots’ out of black fondant. I started with a couple of circle cutters for the black spots to make life easier, but you could use a shot glass or bottle cap if you don’t have circle cutters on hand. I used a cut coffee straw to make the smallest spots. Free-handing the spots is also an option. Adhere to the frosting in a bit of a random ‘Dalmatian’ pattern.