Chocolate sheet cake for Annette

     One of my co-workers (Annette) is leaving after working at The Tech for nearly five years.  To say thank you and as a parting farewell, I wanted to bake a cake for her.  I (not so sneakily) asked her what kind of cake she liked the best, and she said chocolate.  Not being the hugest fan of chocolate cake, I had a bit of a hard time figuring out which recipe would be the best to feed both her and our other co-workers for her final day celebration.  Scanning through my multiple cookbooks, I decided to go with a chocolate cake recipe from The Complete America's Test Kitchen TV Show cookbook.  I inherited this cookbook from our former boss, so I thought it seemed especially appropriate.

So rich and chocolaty!

Chocolate Sheet Cake with Easy Chocolate Frosting (from The Complete America's Test Kitchen TV Show Cookbook)

Ingredients:

For the Cake:

12 tbsp (1.5 sticks) unsalted butter

3/4 cup dutch processed cocoa powder
1 1/4 cup AP flour
1/2 tsp baking soda

1/4 tsp table salt

8 oz semisweet chocolate, chopped

4 large eggs, at room temperature

1 1/2 cups granulated sugar

1 tsp vanilla extract

1 cup buttermilk

For the Frosting:

1/2 cup heavy cream

pinch table salt

1 tbsp light or dark corn syrup

10 oz milk chocolate, chopped

1/2 cup confectioners sugar

8 tbsp (1 stick) cold unsalted butter, cut into 8 pieces

Procedure for the cake:

1) Adjust an oven rack to the middle position and heat the oven to 325 degrees F.  Grease a 13" x 9" baking pan, then line the bottom with parchment paper.

2) Sift together the cocoa, four, baking soda, and salt in a medium bowl; set aside.  Melt the chocolate and butter in a heatproof bowl set over a saucepan filled with 1 inch of barely simmering water, stirring occasionally until smooth.  Whisk together the eggs, sugar , and vanilla in a medium bowl.  Whisk in the buttermilk until smooth.

3) Whisk the chocolate into the egg mixture until combined.  Whisk in the dry ingredients until the batter is smooth and glossy.  Pour the batter into the prepared pan; bake until firm in the center when lightly pressed and a toothpick inserted into the center comes out clean, about 40 minutes, rotating the pan halfway through the baking time.  Let the cake cool completely in the pan, set on a wire rack, about 2 hours.  Ruin a small knife around the cake and flip the cake out onto a wire rack.  Peel of f the parchment paper, then flip the cake right side up onto a serving platter.

Procedure for the frosting:

4) Heat the cream, salt, and corn syrup in a microwave-safe measuring cup on high power until simmering, about 1 minute, or bring to a simmer in ta small saucepan over medium heat. 
5) Place the chocolate in a food processor.  With the machine running, gradually add the hot cream mixture through the feed tube; process for 1 minute after the cream has been added Stop the machine; add the confectioners sugar and process to combine, about 30 seconds.  With the machine running, add the butter through he feed tube one piece at a time; process until incorporated and smooth, about 20 seconds longer.
6) Transfer the frosting to a medium bowl and cool at room temperature, stirring frequently, until thick and spreadable, about 1 hour.  Spread the frosting evenly over the top and sides of the cake and serve.

The final product with sprinkles

     This recipe was much easier to make than I thought it would be, although I will admit I did make a huge mess while making it.  I ended up being a little lazy/pressed for time and had parchment paper not only on the bottom of the pan but around the sides as well.  This actually made the cake really easy to remove from the pan (no knife needed!), so I'm glad I ended up doing it that way!  The cake was very rich, chocolaty, dense (but not too dense), luscious, and delicious!  Best of all, Annette liked it (she had two slices when I couldn't even finish one!) and was really appreciative that I made it for her.  We'll miss you, Annette!