Step 1

Preheat the oven to 350°F.  Grease and flour three 6-inch cake pans and set aside.

Step 2

Sift together the flour, cocoa power, baking powder, baking soda, and salt.  Set aside.

Step 3

In the bowl of a stand mixer fitted with the paddle attachment, beat the oil and sugar on medium speed for 2 minutes.  Add the vanilla and eggs, one at a time.  Stop the mixer and scrape down the bowl.

Step 4

Turn the mixer to low and add the flour mixture in three batches, alternating with the milk, beginning and ending with the flour mixture.  Stop and scrape down the bowl.  With the mixer on low, stream in the coffee.  Mix on medium-low for no more than 30 seconds, or until the batter is combined.

Step 5

Evenly divide the batter among the prepared pans.  Bake for 25 to 28 minutes, or until a toothpick inserted into the center of the cakes comes out clean.  Let them cool on a wire rack for 10 to 15 minutes before removing the cakes from their pans.

Step 6

Using a stand (or hand) mixer fitted with the paddle attachment, beat butter on medium-low speed until smooth and creamy (1 to 3 minutes.)

Step 7

Gradually add all but 1 cup confectioners’ sugar, 2 tablespoons of milk, vanilla, and peppermint extract with mixer at low speed, scraping bowl occasionally. Mix until blended.

Step 8

Beat at medium-high speed 3 to 5 minutes, until buttercream is light, airy, and nearly white.  If needed, add the additional powered sugar or milk until desired consistency is achieved.  The buttercream should spread smoothly without tearing the crumb of the cake but think enough that it holds shape when piped and spread between the layers.

Step 9

Place the chocolate, cream, and corn syrup in a small saucepan.  Heat over medium-low until the cream begins to steam and the chocolate starts to melt.  Remove from the heat and stir to combine.

Step 10

Stir in the salt.  Pour the glaze into a heat-safe container and allow to cool and thicken before use.

Step 11

The glaze should be cool enough that it does not melt or run off the cake, but thin enough that it drips naturally down the sides of the cake.

Step 12

In the top portion of a double-boiler or a heat-safe bowl set over a pan of simmer water, melt the white chocolate.  Once melted, stir in the peppermint extract then spread into a thin layer on a piece of parchment paper or non-stick silicone mat.  Allow to dry.

Step 13

Once the white chocolate has set, melt the dark chocolate in the top portion of a double-boiler.  Spread over the white chocolate with an offset spatula and sprinkle with crushed peppermint.  Allow to dry then cut or break into pieces.

Step 14

Place one layer of cake on a cake board or serving dish.  Spread on about ¾ cup of buttercream with an offset spatula until smooth.  Top with the next layer of cake and repeat.  Place the last layer on top of the cake.  Crumb coat the cake with a thin layer of buttercream then refrigerate the cake for 15 minutes.

Step 15

Once chilled, frost the cake as desired.  Test the chocolate glaze by drizzling a small amount off the top ledge of the cake.  Cool or re-heat the glaze accordingly.  To make the chocolate drips, add chocolate glaze around the cake and let set.  Once the glaze has set, decorate the cake with the remaining frosting and pieces of peppermint bark.

Step 16

Serve the cake at room temperature.  Refrigerate leftovers in a cake box or loosely covered with plastic wrap for up to 3 days.