Thursday, June 22, 2006

Chocolate Raspberry Cake

Inspired by a recipe I saw in video on the PBS web site, "Julia Child - Lessons with Master Chefs," I tried my hand at a fancier cake than usual. I was overall pleased by the result. The genoise was light, and complemented the rich mousse and icing nicely. Rasperries added a touch of freshness.

The chocolate raspberry ruffle cake demonstrated by Alice Medrich was a lot more elaborate, and I do hope to follow her instructions fully one day. But for a first time I decided to omit her elegant chocolate decor as well as a layer of whipped cream-covered raspberries. I tucked the raspberries into the chocolate mousse layer sandwiched between two layers of chocolate genoise, and topped the cake with a ganache icing decorated with a white chocolate swirl and raspberries.

The icing is a recipe from Our Pâtisserie. I wasn't sure how the end result would look given I didn't ice the sides, but I like the way you can see what's inside the cake, even if it doesn't look as finished as it might.

Actually I made two of these cakes, one without raspberries or any liquor for children. On the children's cake I tried icing the sides, but either my genoise was too crooked or I don't have the technique down, it looked a little lop-sided. But I had fun writing the birthday girl's name on the cake in white chocolate.

Recipe: Chocolate Raspberry Cake

Source: the cake is inspired by a video demonstration by Alice Medrich.

1. Make the génoise (chocolate sponge cake)

I'll try to be detailed but remember you can view a full demonstration on the link above. I made 1 1/2 recipe to fill two 18 cm molds rather than one 8 inch mold. These increased quantities are in parentheses, in grams. Other than this change I followed the recipe scrupulously, as I know a génoise leaves no room for improvisation.

- 1/3 cup + 1 tbspn flour (74g for 150% of the quantity)
- 1/3 cup + 1 tbspn cocoa (55g)
- 4 eggs (6)
- 2/3 cup sugar (200g)
- 3 tbspn butter (64g)

Preheat the oven to 350°.

Line an 8 inch springform pan with a circle of wax or parchment paper. Don't butter it though. (I think the dough needs to cling to the walls of the pan as it rises).

Sift the flour and cocoa together three times. Doing it into a sheet of parchment paper makes it easy to pour back into the bowl or sifter.

Melt the butter in a bowl that's a bit larger than strictly necessary for the butter (I believe it's supposed to be clarified, I didn't bother).

Whisk the eggs and sugar in a heat-proof bowl large enough to hold them when they triple their volume. Over a hot water bath (make sure the bowl doesn't touch the surface of the water), whisk them until they reach about 105-110°F. This is lukewarm, so they will expand as much as possible. Then beat them with an electric beater until they triple in volume and form a ribbon that keeps its shape for a few seconds. It's quite important not to stop too soon. I would say with my hand-held mixer I beat them for about 8 minutes. Some recipes suggest beating over the hot water bath, I'm not sure if that's necessary.

Add half the flour and cocoa mixture and fold it in very gently, taking care not to deflate the eggs. When the color is roughly uniform, add the rest and fold in. Take a big spoonful of this batter and add it to the melted butter. Carefully fold this in with the butter so that it's homogenous, then add all of this to the main batter and fold gently. A few strokes are sufficient. (This prevents the butter from falling to the bottom of the batter, which has happened to me in the past with my lemon cake).

Gently pour into the prepared pan and bake for about 30 minutes, "give or take 5." Ms. Medrich checked for doneness simply by touching the cake, saying something like "this seems cooked through, it springs back gently and there's not too much moisture beneath the surface." I had trouble guessing at the right time. With my smaller molds, I thought 22 minutes might be enough, but the tops felt very wobbly. Perhaps opening the door too soon made the cakes deflate a bit. I ended up leaving them in for 28 min., which may have been more than enough.

Take the cake out of the oven and let it cool on a rack. Only once it's cool should you try to unmold it. First run a thin plastic spatula around the edges to separate them from the pan. I didn't have one, so I used a thin knife, which may explain the ragged edges on my cakes. Then turn over the cake and peel off the parchment. Be gentle as you do this as the bottom of the cake will become the top when you're done with it.

2. Make the syrup

- 1/3 cup sugar
- 1/3 cup water
- a shot of framboise liqueur (I used Mandarine as I don't have framboise). This is optional. It can be replaced by liquid vanilla and a bit of water if it's too sweet, or by nothing.
Bring the water and sugar to boil. When it cools down, add the liqueur, if using it.

3. Prepare the layers

Cut the cake in two layers. To do this, run a serrated (bread) knife around the cake simply to score it, then cut through (this is demonstrated in the video).

Place the top layer in the spring-form pan, cut side facing up. Dab it with syrup using a pastry brush. I tried to avoid "soaking it silly" but may have had too light a hand, as I didn't really taste it. But I'm not sure it was a loss.

Cover the cake layer with
- 250g? 500g? raspberries,
leaving some room for the mousse to sink between the berries.

This is when you make the chocolate mousse. According to A. Medrich it "can't wait" so it should only be prepared when the layers are ready to be spread with it.

4. Make the chocolate mousse

- 5 ounces good bittersweet chocolate
- 3 tbspn boiling water
- 3/4 cup heavy cream or crème fraîche
Actually, it's 3/4 cup once it's whipped, I don't know how much you need to start with. But if you have some leftover whipped cream, what's the harm? I used heavy cream as I thought some of my guests might not like the sour flavor of the crème fraîche. I forgot to multiply these quantities by 1.5 but ended up with sufficient mousse.

Chill a large bowl in the freezer for 15 minutes. Chill the cream a few minutes in the freezer as well. Then beat to make soft whipped cream.

Chop the chocolate in small pieces. Boil the water and pour on to the chocolate. Mix. The chocolate should be melted and lukewarm (test on your upper lip). Gently fold in 1/4 cup of the whipped cream, then the remain 1/2 cup.

Immediately pour onto raspberries on cake. Push down gently with spatula so the mousse squeezes in between the berries. Careful add the top layer, cut side down. Press a little then refrigerate while you make the icing.

5. Make the icing

Source: Our Patisserie, who used a recipe from Cocolat by... Alice Medrich.

"Mocha Glaze
I am giving you the amount Alice gave in the book for a 8"-10" torte. But I must add that we always have quite a bit left when I am done with glazing. Needless to say, nobody complains. You can always remelt the glaze and use it in a different project. I used semisweet chocolate although Alice says milk chocolate works better with coffee.

- 10 oz milk chocolate, cut into tiny bits (Astrid: I used dark chocolate)
- 3/4 c heavy cream
- 1 tbs light corn syrup (Astrid: I have some (dark) corn syrup from the US. It gives a shiny gloss to the icing. I wonder what I'll use when it runs out.)
- 1 tbs plus 1 tsp powdered instant coffee, dissolved in a few drops of water (Astrid: I left this out)

Put heavy cream and light corn syrup in a pan and bring to simmer. Add the coffee and stir to mix. Take off the heat, add the chocolate and stir until it is smoothly melted. Use at 100F to glaze your torte."

To make the white swirls, gently melt some
- white chocolate
in a small plastic sandwich bag in the microwave. Snip off a small corner, and use as a pastry bag for making a spiral. Then take a toothpick or sharp knife and draw lines in opposing directions. Decorate with raspberries.

Zinnur recommends not putting the cake in the refrigerator if you want to keep the shiny gloss. Given how hot and humid it was the day I made the cakes, this wasn't an option, but the hour or two they spent in the fridge didn't ruin the effect.

For a different decoration on this cake, see this post added later.

PS In reference to my last post, I had no problems with the use of cocoa in this génoise. Perhaps cocoa works best for mild-flavored chocolate cakes?


Kai said...

Nice. Looks like a book!

Astrid said...

Thanks! I had fun making it. But it sure takes a lot of time writing this kind of post!

Anonymous said...

Wow, Astrid - this looks yummy ! How did it taste ?

Astrid said...

Quite good, I think. Though we only tasted one portion at our friends' house, and with talking I didn't pay too much attention. I was given a doggie bag to take home that I then promplty forgot there. Which is probably just as well! Anyway, the kids liked theirs too, which is always encouraging. Though the birthday girl herself had a fever and didn't eat any... L even blew out her candles for her! (She was pleased to oblige).

tanya d said...

So beautiful! I wish I had your attention to detail.

zorra said...

Wow, it looks delicious!

Astrid said...

Tanya -- Look who's talking, when you're capable of knitting intricate works of love!

Zorra -- Thanks! It takes a fair amount of time to make, but that's where a blog helps make the trouble worthwhile.

keiko said...

Hi Astrid, I wish I could decorate cakes this beautifully - looks perfect!

Astrid said...

Keiko, thank you for your comment. I don't know what to say, given I've never known anyone to make such beautiful desserts as yours! I think you could make this icing with your eyes closed and your hands tied behind your back...