Monday, February 2, 2015

The Jackie-OH! Chocolate Cake with Caramel Buttercream

At my pastry shop, I'd roll out new pastries often.  One of my first offerings was a decadent, fudgy chocolate layer cake slathered in caramel buttercream.  We hadn't had the cake in the case more than 2 seconds when a customer remarked, "That's as beautiful and perky as one of Jackie O's pillbox hats."

So it came to be that one of our most popular cakes was named the "Jackie-OH!"  It's elegant and understated with gorgeous hidden depths.  I'd say we landed on the perfect name, alright.

For the cake

3 cups sugar
3 eggs
3/4 cup neutral vegetable oil (like canola)
1 cup piping hot, freshly brewed coffee
3 ounces bittersweet chocolate, 60-70%, finely chopped
1 1/2 cups all purpose flour
1 cup cake flour
1 1/2 cups Dutched cocoa (I use Cacao Barry Extra Brute)
1 1/2 cups lowfat buttermilk, room temperature
2 teaspoons baking powder
1 teaspoon baking soda
1 teaspoon salt
1 teapsoon vanilla

Line the bottom of four 9" cake pans with a round of parchment and spray with non-stick cooking spray.  Set aside.

Preheat the oven to 325ºF.

Place the chopped chocolate in a heat proof bowl.  Pour the coffee over the chocolate to cover completely. Allow to sit undisturbed to melt.  Set aside.

In a large bowl, combine both flours, cocoa, baking powder, baking soda and salt.  Whisk at least 30 seconds to combine.

In the bowl of a stand mixer combine the sugar, eggs and oil.  Whisk on high until lightened and combined.

Stir the chocolate and coffee mixture, making sure that the chocolate has completely melted.  If chunks of unmelted chocolate remain, briefly microwave on low power to completely melt the stray bits  Add the chocolate mixture and vanilla to the buttermilk and stir to combine.

With the mixer running on low speed, add 1/3 of the flour mixture to the stand mixer and mix just to combine and then add 1/2 of the chocolate/buttermilk mixture.  Continue alternating between the buttermilk mixture and flour mixture until they are both completely incorporated into the batter.

Divide the batter among the 4 pans evenly.  To get the batter perfectly divided, I weigh my mixing bowl before getting started and then weigh the batter filled mixing bowl once the batter is complete and subtract the weight of the bowl from the total.  What's left, you divide by four.  In my case, I ended up adding 16.75 ounces to each pan.

Bake for 25-30 minutes or until the cakes just spring back when gently poked.  Allow to cool completely.

For the Italian caramel buttercream

2 cups sugar
1/2 teaspoon salt
10 egg whites
1 teaspoon vanilla
squirt lemon juice
1 pound 8 ounces unsalted butter, room temperature

In the bowl of a stand mixer fitted with the whisk attachment, combine the egg whites, vanilla and salt.

In a heavy bottomed and large saucepan, combine the sugar, 1/2 cup water and the squirt of lemon juice.  Stir over low heat until the sugar has completely melted.  Stop stirring and raise the heat to medium-high.  Cook the sugar until it turns a medium deep amber.  Have 1/2 cup room temperature water on standby.

Once the sugar has turned the appropriate amber, take the caramel from the heat and CAREFULLY add the 1/2 cup of reserve water.  The mixture will spatter and bubble vigorously so be very careful in doing this.  The mixture will settle down quickly.  Once the carmel has stopped erupting, attach a candy thermometer to the side of the pan and stir over low heat to ensure any hardened bits of caramel melt.  Heat the mixture until the temperature reaches 234º-240ºF.

Turn the mixer on high and whisk the egg whites until they become foamy, carefully pour the caramel syrup down the side of the bowl and into the whisking egg whites until all the caramel syrup is added.  Whisk until stiff peaks form and the bowl is cool to the touch.

Adding butter to the point that the meringue has turned liquidy and starting to look a bit curdled.  

Add the butter, a few tablespoons at a time, with the mixer running on medium speed.  Allow each addition to incorporate until adding more.  The meringue will deflate at first and start to look more "liquidy."  This is normal.  It will often then start to look broken or curdled.  This is also right on the money.  At this point, add a few more tablespoons of butter and mix on high until the buttercream thickens and smooths out.

Finished Buttercream

To assemble

Sugar pearls (optional)

Place a layer of cake onto a cake stand.  Spread a little over 1 1/2 cups buttercream in an even layer over the cake layer.  Continue building the cake like this, adding a layer and then 1 1/2 cups buttercream until all four layers are on the cake.  Spread a thin, crumb coat, over the top and sides of the cake and refrigerate to set, about 15 minutes.

Spread all but 1/2 cup of the remaining butter cream in a smooth finishing coat over the remainder of the cake and then, using a pastry bag fitted with a small open tip, add the remaining buttercream to the bag and pipe beads along the perimeter of the top of the cake and along the bottom of the cake.  Refrigerate to set, about 20 minutes.