Troika Cake

Den norske versjonen av dette innlegget finnes her.

The Norwegian Nidar chocolate “Troika” is one of my favorites. It consists of chocolate truffle, marzipan and raspberry jelly. Recently, I have repeatedly seen that it is possible to make a cake inspired by this chocolate. The idea is to have a chocolate base resembling chocolate truffles, then a layer of marzipan, then a layer of red jelly and ultimately some form of chocolate coating. Here I made my version of this cake. First, a thin pie crust with cocoa, to give the cake some robustness. Then a layer of ganache, followed by a layer of white, homemade marzipan, then a layer of homemade raspberry jelly. Finally the cake is covered by a coating of melted chocolate. If the almonds are shelled and dried, and the raspberry puree has been made ready in advance, it takes not more than 1 1/ 2 hours to finish the cake. But you should probably expect to spend some more time the first time you try this cake. Constructing a cake layer by layer is unfamiliar to most people. The recipe is sufficient for about 8 people and gives a cake of 18cm in diameter.

Pie crust:
50 g (gluten-free) oats
15 g cocoa
35 g (milk-free) margarine or butter
25 g icing sugar
15 g apple sauce (cooked apple without sugar)
1/8 teaspoon salt
Put the oven at 180 gC. Process oatmeal in a blender until it becomes a fine meal. Add the cocoa and chunks of margarine and run the blender until the margarine is finely distributed in the flour. Pour the mixture into a mixing bowl and stir in icing sugar, salt and applesauce. Mix until you have a firm dough. Use a baking tin, 18 cm in diameter, and grease the bottom with oil or milk-free margaarine. Use your fingers to spread the dough flat onto the bottom of the baking tin. Bake the pastry at 180 gC for 13 to 15 minutes, until it has become slightly firm to the touch. Place the base on a cake stand.

Chocolate ganache:
100 g 70 % chocolate without milk
100 g coconut milk 17 % fat
1 tablespoon vanilla extract
Put the coconut milk with vanilla sugar in a small saucepan and bring to the boiling point. Remove from heat and stir in chocolate until melted. Pour the mixture into a bowl and let cool. Just before you assemble the cake, you can whip up the chocolate ganache with a handheld mixer, until it is so thick that it can be spread out over the cake bottom with a spatula.

Marzipan:
75 g shelled, dried almonds (or use finely ground almond flour)
75g icing sugar
1 teaspoon Certo freeze powder (contains 50 % xanthan, is used in Norway for making marmalades without boiling the berries),
1 tablespoon (15 g) of water
Almonds should be prepared in advance, to ensure they are completely dry: Boil the almonds for 1-2 min. Remove the shells. Place the almonds in a baking dish and put them in the oven to dry at about 50 gC for a few hours. Alternatively, almond flour can be used. Process the almonds with icing sugar and Certo freeze powder (or xanthan) in a blender until it becomes a fine powder. Add 1 tablespoon water and blend some more seconds, until the mixture comes together as a dough. Scrape the mixture out of the blender, and assemble into a firm dough. Roll out the marzipan into a round circle, 18 cm in diameter. Use the bottom of the cake tin as a measuring stick.

Raspberry Jelly:
175g raspberries (fresh or frozen)
75 g water
50 g sugar
15 g hydrated 10% agar mixture (see comment below) or 3 sheets of gelatin
Have the rasberries and water into a cooking pot and bring to a full boil. Strain through a sieve to remove raspberry seeds. Have the berry puree back into the pot, it should be about 200 g raspberry puree, if necessary add a little more water. Add the sugar and agar and bring to a boil again. Simmer and stir untill the agar is completely dissolved. It can take 2-3 minutes. Cool the gel to about 50 gC and keep it at this temperature until ready to assemble cake. Then cool the mixture in cold water bath, until you see that it starts to thicken. It goes pretty fast. Pour it as soon as it starts to thicken onto the marzipan on the cake base (see instruction for assembly of the cake below).

If using gelatin, soak the sheets in cold water for 2-3 minutes before adding them to the boiling raspberry puree. Stir well until the gelatin is completely dissolved. Cool the mixture completely in cold water bath and wait until it begins to thicken before you pour the jelly over the marzipan (see below).

Chocolate cover:
100 g 70 % chocolate without milk
25 g coconut milk
Melt chocolate over a boiling water bath, stir in the coconut milk. Spread the mixture over the cake (see below).

Assembling the cake:
Place the pie crust on a cake stand. Put the ring of the baking tin around the cake. Cover the side of the ring with waxed paper or plastic foil, if you have that available. Spread the ganache over the pie crust. Place the marzipan over the ganache. Pour over the raspberry jelly that has started to solidify. Make sure the cake is horizontal, to avoid that the jelly stiffens obliquely on the cake. Put the cake cool so jelly and ganache gets solidified. Remove the ring of cake tin, remove any plastic foil around the cake. Mix together the ingredients for the chocolate cover and apply it evenly over the cake and on the sides with a spatula or a dough scraper. Eventually garnish with some fresh raspberries.

This cake is gluten-free (if you use gluten-free oats), milk-free (if you use milk-free margarine) and egg free. If using agar cake is also vegan and halal.

If you tolerate milk, you can use cream instead of coconut milk ganache (use as much cream as you would have used coconut milk although fat percentage is a little different). If you tolerate eggs, you can substitute the cooked apple with 1 egg yolk in the pie crust and in the marzipan you can replace Certo freeze powder (or Xanthan) and water with a half whipped egg white. If you want to replace sugar with alternative sweeteners, it will work just fine in this cake, since sugar here only contributes with flavor.

Hydrated 10% agar:
Agar is sensitive to pH, and is also used in so small quantities that it may be difficult to measure the correct amounts. 0,5 g agar will replace one sheet of gelatin. In this recipe, 1,5 g agar is needed.

To facilitate measuring agar, and also to reduce the sensitivity of the agar to low pH, it is helpful to make a 10% hydrated agar upfront. Weigh in 10 g agar and 100 g water in a cooking pot. Bring to a boil, while stirring constantly. When the mixture comes together and becomes thick, take the pot off the heat and let the mixture cool. Hydrated 10% agar may be kept in the fridge for several weeks in an airtight container.

One word of caution here though, the quality of the agars may differ considerably. The one I use, from Texturas, work nicely. However, one of my readers has complained that this method does not work well with her agar, since the 10% hydrated agar becomes very difficult to redissolve. An alternative strategy is thus that you use a 1 ml spoon and count how many ml there is in 10g agar. For Textura’s agar, 1ml is 0,5 g.

Another word of caution: If you go for dissolving agar directly in the fruit puree, it will work fine, as long as the pH is not too low. Low pH results in fragmentation of the agar, and loss of gelling capacity. I my experience, raspberry juice may have a too low pH for this to work. In that case, hydration of the agar in pure water before adding the berry puree may be a way around the problem.

Blogpost by Anne Spurkland, published on the 19th May 2013
English edited version of blogpost published 26^th February 2014