Introduction: Frozen Blueberry & White Chocolate Cake Wrapped in White...
...chocolate with a lemon sauce
right now there are blueberries in abundance where i live, so why not make something nice with them?
so to match the crazy temperatures (just some days ago it was the "hottest day of the year", let's see if hotter days are still to come...) why not make something frozen.
this dessert has it all: crispy chocolate wrapping and almonds, creamy ice cream filling topped with a fruity berry sauce!
it is a lot of work - but worth every minute of it! don't let the many steps keep you from making it, some of the things can be prepared in advance.
some of the inspiration for this dessert came from a cooking book i once found at a fleamarket. i really love this book, the dessert ideas alone are worth getting it!
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Step 1: Ingredients
for 4 portions you need:
for the biscuit sponge:
- 3 eggs
- 90 g sugar
- 45 g flour
- 45 g starch
- 60 g sliced almonds
for the white chocolate ice cream and the white chocolate wrap:
- 200 g white chocolate
- 200 ml whipping cream
- 1 egg yolk
- 30 g sugar
for the blueberrys:
- about 3 cups of blueberrys
- juice of 1/2 lemon
- 100 ml of simple syrup (to make the syrup, boil sugar and water until the sugar is dissolved, then leave to cool. ratio is 1,2 kg of sugar per 1 l of water, scale down to your needs)
for the lemon sauce:
- zest of 1 lemon
- 2 egg yolks
- 30 g sugar
- 200 ml milk
Step 2: Go Blueberry Picking!
right now (end of july, august) is the time when blueberrys will be ripe (in the northern hemisphere).
so if you are lucky enough to live close to a forest where the blueberrys grow go out and pick some! they will taste a lot better than bought ones.
so when i went to the woods, i was lucky enough to not only find blueberrys, but also lots of lingonberrys as well.
there is always a risk of poisoning or catching diseases from collecting plants or mushrooms in the wild. if you are not sure what blueberry plants do look like (just because it is blue and the size of a blueberry and grows in the wood does not mean it is a blueberry everytime) just buy fresh or frozen blueberrys in the store.
Step 3: The Sponge
preheat the oven to 180 degrees (celcius).
separate the eggs, put the egg yolks in a bowl and add the sugar. with a grater, zest the lemon into the bowl.
whisk the sugar and yolk mixture until pale and fluffy.
add starch & flour and mix until blended.
in another bowl, put the egg whites and a pinch of salt and whisk until very stiff (be sure to clean the whisks before, since any fat left on the whisks will prevent the egg whites from beoming stiff), then carefully fold the egg whites into the yolk mixture.
line a baking tray with baking paper and spread the sponge mass evenly onto the tray to a rectangle of the size of about 18 cm x 36 cm. sprinkle the top with half of the sliced almonds.
put the tray in the oven and bake for about 15 - 20 minutes until the top is golden brown. leave to cool.
the sponge could be made one or two days in advance, in this case wrap in in cling film an store in a cool place.
Step 4: The Chocolate Cream
chop 150 g of the white chocolate finely.
keep the rest of the chocolate for later. (step 8)
put 50 ml of the cream in a pot and bring to boil. remove from the stove and add the chocolate. when the chocolate is dissolved add sugar and egg yolk.
whip the rest of the cream until stiff then fold into the chocolate mixture. put in the fridge until you assemble the cake.
the cream should be made the same day you want to assemble the cakes.
Step 5: Prepare the Blueberrys
if you picked your own blueberrys, wash them thoroughly to get rid off all the leaves & bugs that sneaked their way into the bag.
put half of the blueberries in a high and narrow container.
add the simple syrup and the juice of half a lemon. blend with a handheld blender until well blended. you now have blueberry sauce.
filter the sauce through a fine mesh sieve into the bowl with the rest of the blueberrys. put the blueberry-sauce mixture in the fridge until you assemble the cake.
you could prepare the berrys 1 or 2 days in advance.
Step 6: Assemble!
get all your single elements: the sponge, the berrys in the sauce, the chocolate cream.
because the cake will be not so easy to transport while not frozen yet, find a board that fits in your freezer and cover it with baking paper in case there will be some spilling.
cut two squares with a side lenght of 14 cm out of the biscuit sponge. take a piece of aluminium foil of about 30 x 30 cm and put one of the sponge squares in the middle. put on the prepared board and form a "box" with the aluminium foil around the sponge square (see picture).
now put half of the berry-sauce mixture on top of the sponge in the foil. put almost all the chocolate cream on top, then put the second sponge square. put the rest of the chocolate cream.
now the cake is ready to be frozen.
with the board, put the cake into the freezer and freeze for at least 8 hours.
you can freeze the cakes for some days at this point, but the longer you freeze them, the harder (and less easy to eat) the ice filling will become.
put the rest of the berry sauce back in the fridge.
Step 7: The Lemon Sauce
while the cake freezes, make the lemon sauce:
put the milk in pot. grate the lemon zest into the milk and bring to boil. put the egg yolks and the sugar in a bowl and whisk until pale and fluffy. bring the milk to boil, once the milk boiled pour it slowly into the egg & sugar mixture, stirring all the time. clean the pot, put the mixture back into the pot and heat over a low flame until it thickens slightly, stir all the time!
remove from the stove, stir in 2 tablespoons of the blueberry sauce to give the lemon sauce a slighly lavender color and then strain through a fine mesh sieve to get rid of the lemon zest.
put into the fridge.
roast the rest of the sliced almonds in a dry pan until golden and fragrant. set aside.
do both on the day you want to serve the cakes.
Step 8: It's a Wrap!
wrapping can take place when the cake has been in the freezer for at least 8 hours.
chop the rest of the chocolate and melt it either in a bain marie or a microwave.
cut four strips of aluminium foil 30 cm long and about 10 cm wide. fold in half lenghtwise (so you have strips 5 cm wide and 30 cm long).
take the cake out of the freezer. peel the aluminium foil away and cut the cake into four squares with a side lenght of 7 cm (cut into quarters). if the cake is not a perfect square to begin with because the aluminium foil gave way a bit, trim the sides first. (i forgot to take a picture of that).
you have to work quite fast now, because as soon as the cake is out of the freezer it will start to soften and eventually melt.
take one prepared strip of foil and with a spoon, coat it evenly with 1/4 of the white molten chocolate along the whole lenght and a little bit higher than the cake.
wrap the foil all around of one of the four cake-squares. the edges should not overlap. (see picture)
repeat with the other three cakes.
put the cakes back into the freezer and freeze for at least another 2 hours.
after that second freezing period, you can peel of the foil and the chocolate will be hardened and stick to the cake, creating a thin chocolate wrapping around the cake.
Step 9: Serve!
when you are ready to eat your delicous ice cakes after all that work lay out four plates. pour 1/4 of the lemon sauce onto each of the plates. then, one by one, take the cakes out of the freezer and carefully peel away the aluminium foil. place the cakes in the middle of each plate on top of the sauce.
spoon 1/4 of the remaining blueberry mixture on top of each cake and sprinkle with the toasted almond slices.
save immediately and enjoy!