You can easily use frozen blueberries to make your purees but you must use fresh one for your decoration because the frozen one will dampen your cake too much. As for the decoration, use either the meringues or the whipped cream because the meringues will absorb the humidity of the cream and will get soft and melt.
Ingredients for a 10x3 cake
Decoration
250 g fresh blueberries (125 g on top, 125 g in one layer)
Whipped cream
300 g cold heavy whipping cream
60 g sugar
Vanilla
Or
Meringues
1 egg white
33 g granulated sugar
33 g confectioner’s sugar
Optional filling
Light vanilla cream
82 g whole milk
1/2 vanilla bean
23 g egg yolk
23 g sugar
8 g cornstarch
8 g butter
0.5 gelatin sheet Dr. Oetker (1 g)
83 g cold heavy whipping cream
Blueberry syrup
100 g blueberry puree
50 g mineral water
50 g sugar
Sponge cake
80 g egg yolk
160 g egg white
120 g all-purpose flour
120 g sugar
Confectioners' sugar
Blueberry quark mousse
150 g blueberry puree
40 g sugar
9.5 gelatin sheets Dr. Oetker (19 g)
43 g mineral water
85 g egg yolk
165 g sugar
425 g quark 30% fat (you can replace it by unsalted cottage cheese)
510 g cold heavy whipping cream
Sugar
Method
Decoration
Whipped cream
- Whip together the whipping cream, the sugar and the vanilla until stiff.
- Put the whipped cream in a pastry bag with the decorating tip of your choosing.
Or
Meringues
- Preheat the oven to 302°F.
- Whisk the egg whites with a little bit of sugar.
- When they are enough whisked, add the sugars little by little so as to obtain a smooth and white meringue.
- Put the meringue in a pastry bag, make some small balls and brown them with a blowtorch.
- Turn off the oven and put the meringue inside with the door still open to dry them.
Blueberry syrup
- Mix together all the ingredients in warm water to allow the sugar to dissolve.
- Put aside.
Sponge cake
- Preheat the oven to 390°F.
- Whisk the egg whites to soft peaks in a stand mixer (Cuisinart or KitchenAid) on high speed.
- Add the sugar little by little until the egg whites are very firm.
- Beat the yolks with a fork and add them to the egg whites. Whisk for 5 seconds on slow speed.
- Add the sifted flour and fold delicately with a spatula.
- Take a pastry bag with a smooth decorating tip (1 cm wide) and make two 10.5-inch biscuits on wax paper. Sprinkle with confectioners' sugar and bake for 10 minutes.
- Let it cool on a cooling rack then cut the biscuits with a 9-inch ring.
Filling
- Light vanilla cream
- Split the vanilla bean in two and scrape the seeds into the milk. Bring to a boil and let it infuse 15 to 20 min.
- Hydrate the gelatin in cold water.
- Meanwhile, beat together the yolks, the sugar and the cornstarch without whitening or frothing.
- Boil the milk again and pour 1/3 into the eggs, blend, add in the rest and blend.
- Put it back into the pan by pouring it through a strainer and beat over high heat until it thickens.
- Remove the pan and add the butter.
- Cool it rapidly stirring the whole time so as to prevent the cream from drying.
- Once it is cool, whip the cream and fold it gently in the pastry cream.
- Pour the cream over the first soaked biscuit in a 9-inch wide ring. Add 125 g of fresh blueberries.
Blueberry quark mousse
- Hydrate the gelatin in cold water.
- Whip the egg yolks with an electric mixer on high speed.
- Boil the water with the sugar to 244°F, pour immediately on the yolks and beat until it cools to room temperature.
- Blend the quark, the blueberry puree and 40 g of sugar.
- Melt the gelatin in the microwave without boiling and add in the blueberry mixture.
- Add to the yolks.
- Whip the cream and fold it gently in the blueberry cream.