Sunday, August 24, 2008

Friday, August 22, 2008

Chocolate Mousse Cake


My friend Kate and I were walking around and I stopped at Whole Foods to pick up some eggs. As we walked towards the register, Kate commented about how fascinating the water aisle is and I remembered a $4 .5 liter bottle of water I'd seen. I couldn't find it though, so I walked us over to the refrigerated water. It still wasn't there.

However, in the process, we walked past the bakery case. "I can't look at it," Kate had said. Me, being the mean friend I am, asked her why not. "Because I always want to buy one." So I told her to pick one out and I'd make it. She picked out one with a flower on top, and then a different one called "Death By Chocolate" and then looked at a mango lime mousse cake. "That seems too weird."

We settled on a chocolate mousse cake. And here it is:

Chocolate Mousse Layer Cake
(cake adapted from The Cake Book by Tish Boyle, mousse from Cooking Light, and ganache from The Cake Book)
makes 1 5" square cake

For cake layers:
2/3 cup (80 g) all-purpose flour
1/4 cup + 2 Tablespoons (30 g) natural cocoa powder
5/8 teaspoon baking powder
1/4 teaspoon baking soda
1/8 teaspoon salt
3/4 cup + 1 Tablespoon (176 g) granulated sugar
2 Tablespoons + 2 teaspoons (40 ml) vegetable oil
1 large egg
2 Tablespoons + 2 teaspoons (40 ml) whole milk
1 teaspoon vanilla extract
1/2 cup (120 ml) boiling water

For chocolate mousse:
1 (12.3 oz) package firm silken tofu
4 1/2 ounces bittersweet chocolate, melted
2 large egg whites
1/4 teaspoon salt
1/2 cup sugar
1/4 cup water

For bittersweet chocolate ganache:
6 ounces (170g) bittersweet chocolate, chopped
2/3 cup heavy cream
1 teaspoon vanilla extract

To make cake:
Position a rack in the center of the oven and preheat oven to 325ºF. Line a 10-inch square baking pan or 2 9x5 inch loaf pans with parchment and grease bottom and sides of pan and dust with flour.

Sift together the flour, cocoa powder, baking powder, baking soda, and salt into a medium bowl. Whisk in the sugar. At a low speed, using a mixer, beat in the oil for a few seconds until dry ingredients are crumbly.

In a small bowl whisk together the eggs until blender. Whisk in milk and vanilla extract. With the mixer at low speed, add egg mixture to flour mixture and mix until blended, scraping down sides of bowl as necessary. Gradually add the boiling water and mix just until blended and smooth. Pour the batter into the prepared pan (or pans.)

Bake the cake for 25 minutes (for two loaf pans) or until toothpick inserted in center comes back clean or it bounces back if lightly touched. Cool the cake in the pan on a wire rack for 10 minutes. Invert the cake onto the rack (or using parchment paper, if made withe handles, remove) and cool the cake completely.

To make the mousse:
In a food processor, mix together the tofu and melted chocolate until smooth, about two minutes.

In a medium bowl, beat the egg whites and salt until stiff peaks form. In a small saucepan combine sugar and water and bring to a boil. Cook, without stirring until a candy thermometer reaches 250ºF. Slowly pour syrup into the egg whites while beating.

Fold in 1/2 of the meringue into the chocolate tofu mixture. Fold in remaining meringue, cover with plastic wrap, and store in refrigerator until ready to use.

To assemble cake:
Cut cake into four squares (or each loaf cake in half). Place on a small piece of cardboard cut to size and top with 2/3 cup of mousse. Place in freezer for fifteen minutes. Top with cake layer and mousse. Freeze for fifteen minutes; repeat with remaining cake layers. Freeze for thirty minutes after final layer of mousse.

Meanwhile, in a small saucepan, bring 2/3 cup cream to a simmer. Remove from heat and stir in 6 ounces chopped chocolate until smooth. Stir in vanilla extract. Let sit ten minutes.

Place cake on a wire rack and pour chocolate ganache over it. Spread to cover top and sides of cake. Decorate with whipped cream and chocolate curls if desired. Refrigerate for at least 2 hours before serving.