Chocolate Cake with White Chocolate Mousse and Sour Cream Ganache

Chocolate Cake with White Chocolate Mousse and Sour Cream Ganache
Adapted from Sky High
Serves: 10 million people
Prep time: 40 minutes
Cook time: 20 minutes
Cost: $1.83 (not bad for 3 layers, but the rich toppings make it expensive) With the frostings it comes to $6.81
(flour: .20, cocoa: .50, chocolate: .40, milk: .13, mayo: .25, sugar: .35)
And, no, I'm not counting this for our cheap eat challenge--It was a gift to Kip. Yes, that's a loophole that I'm using shamelessly. Forgive me.

2 1/4 C flour
1 C cocoa
2 1/4 tsp baking soda
1 1/4 tsp baking powder
1 tsp salt
1/2 tsp cinnamon
2 1/2 oz unswetened chocolate, coarsely chopped
1 C milk
1 1/4 C water
1 C mayonnaise (this makes the batter not as yummy as batter usually is; don't worry; cooking will fix it)
1 1/2 tsp vanilla
2 1/4 C sugar

Preheat oven to 350 degrees. Spray or butter three 9 inch pans, then line them with wax paper on the bottom and spray or butter the wax paper.

In a saucepan, heat milk and water until hot. It shouldn't be boiling, but nearly so--a few small bubbles should be on the edges of the pan. You'll want to stir this regularly, but while it warms you'll have time to sift the dry ingredients.

Sift flour, cocoa, baking soda, baking powder, salt, cinnamon.

When milk and water are hot, pour them over the chopped chocolate. Give a whisk and whisk occasionally until chocolate is incorporated.

In large bowl, beat together eggs, mayo, and vanilla. Gradually beat in the sugar. Add the dry ingredients and the chocolate liquid alternately in about 2 additions. Beat until smooth and well blended. Divide the batter among the three pans.

Cook for 15-20 minutes. (The original recipe recommended 25-28. That would have totally ruined my cakes. I don't know if my oven's wonky or not, but always always check your cakes way before the recommended bake times.)

Remove when a tester or knife comes out clean or with just a moist crumb or two attached.

Cool cake in pans for 10 minutes. Then cool on racks the rest of the way.

When cool, you can assemble the cake.

Sour Cream Ganache
Cost: $3.20
(chocolate: 2.00, butter: .50, half and half: .20, sour cream: .50)

Note on sour creamliness: I tried a sour cream icing before and though it was nasty--not sweet enough and too sour creamy. This one is absolutely awesome. It is much more chocolate than sour cream and that is just what we like in these parts. And the advantge of the sour cream: it makes it just a little looser than normal ganache, which is nice for a cake.

Note on dairy: Also, the half-and-half and sour cream are best at room temp because the mixing is easier and because it doesn't harden as fast, making icing the cake easier. But I forgot and mine were cold and all was well, though it was a bit clumpy getting it on the cake.

12 oz semisweet chocolate
1 stick butter
2 Tbsp light corn syrup
1/4 C half-and-half (best at room temp)
1/2 C sour cream (best at room temp)

Combine chocolate, butter, and corn syrup in microwave safe bowl. Microwave at 30 second intervals stirring in between until chocolate is melted and mixture is smooth (and not to crazy hot). Whisk in half-and-half (or half milk and half cream) and then sour cream. Spread on cake while it is soft. It will get much stiffer and become unspreadable as it cools, so don't wait.

White Chocolate Mousse
Cost: $1.78
(white chocolate: .67, cream: 1.00, egg: .10, sugar: .01)

4 oz. white chocolate, chopped
1 C heavy cream
1 egg white
1 Tbsp sugar
several drops food coloring (optional)

Combine white chocolate and 1/4 C cream in microwave. Microwave in 20 second intervals, stirring between, until chocolate is melted. Add a few drops of food coloring if desired. We gave it a good dose of red to get our pinky pink. And, you know, St. Patrick's Day is coming. Cool to room temperature.

Beat remaining 3/4 C cream until stiff peaks form (you don't want butter or anything, but the stiffer your peaks, the better your mousse will hold up as a frosting).

Combine egg white and sugar. Beat until egg white forms fairly stiff peaks.

Fold egg mixture into chocolate. And then fold in the whipped cream.

To Assemble:

(Remember, I'm recommending the opposite of what I actually did, so don't get confused by the pictures above.)

Place one layer of the cake on a large plate or cake stand. Frost top (not sides) with ganache. (If ganache isn't your thing, you can use another firm frosting like either of these.) Repeat with second layer. Add a thin layer of ganache on top layer if desired.

Top with mousse and dab it onto sides, spreading it around. (Again, be sure you got it thick enough that it won't just slither down the sides. If you didn't because, you know, we're all human, just put it on the top or serve it as a lovely dollop on the side when you serve the cake).

Serve the cake within a few hours or refrigerate it so that your mousse doesn't start melting and getting all funky on you.