Mint Chocolate Layer Cake

It's rare that you eat a piece of chocolate cake and feel as refreshed as if you had just brushed your teeth.  But mint does that, even when it's combined with lots of chocolate.  I've been using the chocolate and mint flavor combination a lot recently, and only by request, but I just may be coming around to this dynamic duo myself.

No picture of the inside of the cake, as it was an order - but I really like the look of the white filling against the dark cake layers.  And if you're really feeling adventurous, dye the filling green!

This recipe is for a 2-layer 6" cake.   You can double the recipe for a 3-layer 9" cake.

Chocolate Cake (adapted from Bon Appetit)

1 1/2 ounces fine-quality semisweet chocolate
3/4 cups hot brewed coffee* 

1 1/2 cups sugar  
1 1/4 cups all-purpose flour  
3/4 cups unsweetened cocoa powder (not Dutch processed)  
1 teaspoon baking soda  
scant 1/2 teaspoon baking powder  
3/4 teaspoons Kosher salt
2 large eggs (use 3 eggs rather than 4 if you double the recipe)
3/8 cup (that's 1/4 cup plus 2 tablespoons, or 6 fluid ounces) vegetable oil
3/4 cup well-shaken buttermilk  
scant 1/2 teaspoon vanilla extract


*You can replace the coffee with half whole milk, half water if you're baking for kids.  The coffee flavor is barely discernible in the cake, it just enhances the flavor of the chocolate.

Preheat the oven to 300°F and spray 2 6" pans with baking spray. Line bottoms with rounds of parchment paper and spray paper as well (you can get away without the parchment paper if you spray the pans very well and if your pans are good quality).

Finely chop the chocolate and place in a medium bowl; pour hot coffee over the chocolate. Let stand for one minute, then stir until chocolate is melted and the mixture is smooth.

Whisk together the sugar, flour, cocoa powder, baking soda, baking powder, and salt in a large bowl.

In another large bowl, with an electric mixer, beat eggs until thickened slightly and lemon colored (about 3 minutes with a standing mixer or 5 minutes with a hand-held mixer).

Slowly add oil, buttermilk, vanilla, and melted chocolate mixture to eggs, beating until combined well.

Add sugar mixture and beat on medium speed until just combined well.

Divide batter between pans and bake in the middle of oven until a tester inserted in center comes out clean, 50-65 minutes.

Cool the cake layers completely in pans on racks. Run a thin knife around edges of pans and invert layers onto racks. Carefully remove parchment paper and cool layers completely.



Mint Filling

1 stick butter (4 ounces), room temperature
1 teaspoon vanilla extract
3/4 teaspoon mint extract (or 1/4 teaspoon mint oil)
3 cups (about 12 ounces) powdered sugar
3-4 tablespoons milk


In a large bowl, cream the butter with an electric mixer.  Add the vanilla and mint extracts.  Gradually add one cup of sugar,  beating well on medium speed. Scrape the bowl.  Add the remaining sugar, alternating with the milk, beginning and ending with the sugar.


Add more powdered sugar to make the frosting stiffer, more milk or water to make frosting creamier.

To save time or to really overload on the chocolate, you may want to use the mint chocolate frosting to fill the cake as well. I personally like to cut the chocolate a little with a different filling.



Mint Chocolate Frosting

4 1/2 tablespoons butter (2 1/4 ounces)

2 ounces unsweetened chocolate

2 ounces semisweet chocolate

A pinch of salt

1 teaspoon vanilla extract

3/4 teaspoon mint extract (or 1/4 teaspoon mint oil)

3 cups (about 12 ounces) powdered sugar

3 ounces (1/4 cup + 2 tablespoons) milk, heated to lukewarm

Beat butter on medium speed for 1-2 minutes.

Blend in the melted chocolate, salt, vanilla, mint, and 1 cup powdered sugar.

Add in the rest of the powdered sugar in three additions, alternating with the milk in two additions (begin and end with the powdered sugar). Add more powdered sugar for heavier (this may be necessary if you want to pipe your frosting) frosting, or more milk for a creamier frosting.  Use immediately.

Assembly

Be sure to chill the cakes before frosting.  Place a layer of chocolate cake on a plate or cake board, and place scraps of parchment paper between the cake and plate/board.  Spread a thick layer of mint frosting on top, leaving a 1/2" border at the edge (the weight of the second layer will cause the frosting to spread towards the edges).  You may have some filling left over.  Freeze for a later use (you can use it in place of the mint layer of chocolate mint brownies).  Top with the remaining cake layer, and chill while you prepare the chocolate frosting.  Frost the cake as soon as the chocolate mint frosting is done - if you can't, you'll need to rewhip the frosting, and you might need to add some milk.

Decorate with shaved chocolate and mint leaves, if desired.