Galaxy Cake is one of the most hyped food trends happening on the social media now. Its velvety mousse cake and the marbled mirror glaze undoubtedly make it a showstopper in the baking scene. When I was working in the industry I used to make many mirror glazed cakes but never got an opportunity to make a Galaxy themed mirror glazed cake. It was only when the ICCA Creative Team came to me with a request for the Galaxy cake recipe; I finally got my hands on it.
It’s the dreamy look and feel of the galaxy that you see on the cake which is created with so many colours such as electric blue, purple, pink, red, black and white, along with star sprinkles and silver & gold edible dust is what made this cake so appealing and popular.
It could be made with any flavor of mousse and I have used blueberry mousse cake layered with Pistachio Dacquoise and coconut nougatine to match with the galaxy theme. So let’s see how the cake is done.
170g castor sugar
120g ground pistachios
50g almond meal
200g egg whites
100g castor sugar
35g brown sugar
260g raspberry purée
20g pectin NH powder (pectin for jams)
220g castor sugar
30g unsalted butter
15g glucose syrup
35g castor sugar
1g pectin NH
40g grated coconut
120g egg whites
405g blueberry purée
40g crème pâtissière
85g cocoa butter
70g white chocolate couverture
350g meringue (ingredients above)
880g whipped cream
100g glucose syrup
65g sweetened condensed milk
100g white chocolate couverture
6g gelatine (200 blooms)
36g water (for the gelatine)
Water-soluble 6 food colouring
Silver iridescent colouring powder
Before starting this Blueberry Mousse Entremets recipe, make sure you have organised the necessary ingredients for the pistachio Dacquoise.
For the pistachio Dacquoise:
- Pour the egg whites into the stand mixer bowl along with the castor sugar and light brown sugar. Add both sugars before starting to whisk and beat on medium speed for a few seconds and then increase to high speed until you obtain a stiff meringue.
- In the meantime, sift the almond flour (which has been slightly roasted beforehand), ground pistachios and castor sugar onto a sheet of greaseproof paper. This operation is important to get rid of clusters of sugar or almond powder. If some bits of pistachios remain, they could be added later to the sifted preparation which will add a nice crunchy effect.
- Pour the sifted mix in a thin stream over the meringue and combine with a rubber spatula folding gently with rotating vertical motions. Make sure the preparation does not collapse!
- When ready, the meringue must be used immediately, hence the need to sift the powders while beating the egg whites.
- When the Dacquoise preparation is ready, pour it into a 16-cm tart rings and bake in a fan-assisted oven at 180 for 12 to 15 minutes.
- Place the butter in a saucepan. Add the castor sugar and glucose syrup. Heat the ingredients to 40°C.
- Add the pectin NH, combined with 5 grams of castor sugar, to the hot preparation. It is essential to combine the pectin NH with sugar first, in order to avoid a grainy consistency. The temperature is also essential to get the right consistency, 40°C being the ideal temperature.
- Cook over medium heat for a few minutes, stirring constantly until it starts to thicken. When the consistency is similar to a white roux (base for béchamel) and large bubbles are formed, add the grated coconut into it and continue cooking over medium heat, stirring constantly.
- Pour the preparation onto a sheet of greaseproof paper and transfer it to a baking sheet and bake at 170°C (gas 3) for 10 minutes until golden and set aside.
- Organise all the necessary ingredients.
- Combine the pectin NH with a little castor sugar. As mentioned earlier, this will avoid lumps due to a poor incorporation of the pectin.
- Pour the raspberry purée in a saucepan. Add the remaining castor sugar and heat up the preparation between 40 and 60°C.
- Using a whisk, add the pectin and mix well, and bring it to a boil.
- Stretch some cling film on 4 tart rings (the ones you used for the Dacquoise biscuit). Do this on one side of the ring only. Pour the marmalade into the rings and put it into the freezer.
- Start by making the meringue.
- Pour the water into a saucepan and add the castor sugar. Cook the sugar until it reaches 121°C. I recommend using a digital thermometer.
- In the meantime, pour the egg whites in the stand mixer bowl and add the castor sugar. This will facilitate the incorporation of the cooked sugar. The sugar is ready when the bubbles have a diameter of about 1cm before bursting.
- Start whisking the egg whites and pour the cooked sugar in a thin stream. Beat until the mixture cools down completely. We will use the meringue later to make the blueberry mousse.
- Put the Mycryo cocoa butter in a mixing bowl. Add the white chocolate chips and set aside.
- Dilute the crème patisserie powder and castor sugar with about 20% of the blueberry purée. Combine well with a whisk until homogeneous.
- Heat up the remaining blueberry purée in a saucepan. When the purée is hot, add the crème pâtissière. Combine well with a whisk until the ingredients are completely incorporated. Leave it to cool at room temperature down to 25°C.
- Place the meringue into a mixing bowl and add the whipped cream. Combine with a whisk.
- Transfer a small amount of meringue cream into the blueberry preparation at 25°C.and combine vigorously with a whisk. This will facilitate the incorporation of all the ingredients.
- Add the blueberry mixture to the remaining meringue. Whisk vigorously, making sure the preparation does not collapse.
Assembling the cake
- Scoop the blueberry mousse into a piping bag fitted with a plain nozzle (diameter 7-8mm).
- Place a Dacquoise biscuit at the bottom of a mousse ring (diameter 18cm).
- Pipe a lace of blueberry mousse along the edge of the ring. To remove any air bubbles, spread with a palette knife and create a volcano shape.
- Cover the biscuit with a layer of blueberry mousse and arrange pieces of coconut nougatine over the blueberry mousse, which will give a nice crunchy effect to the cake.
- Pipe a second layer of blueberry mousse.
- Gently detach the raspberry jelly from the ring and place it on top of the mousse.Gently press on the jelly disc from the center outwards to remove any air bubbles in the mousse underneath.
- Finish with a layer of blueberry mousse on top.Even the surface with a cranked spatula and put it in the freezer. This will allow you to release the cake from the mousse ring easily, simply by heating the sides with a blowtorch.
- Up to this stage, this recipe can be made in advance and stored in the freezer. On the day, simply remove the cake from the freezer and continue with the steps below.
Glaze: (make the day before)
- Pour the water and sugar in a saucepan and add the glucose syrup into it. (It can be melted in the microwave for a few seconds to give it a liquid consistency which will be easier to work.)
- Heat the ingredients until the temperature reaches 103°C. This should be very quick. Basically, the temperature is right when you reach a gentle boil.
- Pour the sweetened condensed milk in a separate bowl and when the preparation reaches 103°C, pour over the condensed milk and combine.
- Add the white chocolate couverture and combine well with a whisk until melted.
- Add the rehydrated gelatine last. It will melt quickly in the warm
- Add some purple colouring powder with the tip of a knife and combine well with a whisk. Colouring powders are very effective. I recommend working with very small quantities, and then adjust the colour by adding more if needed.
- Combine vigorously with a whisk. You will obtain the final color after whisking for a few Refrigerate overnight.
- The following day, process the 6 color glaze, using a hand blender. You should use a deep, narrow bowl. This will allow removing any air bubbles and obtaining a smooth
- Place the cake on a cooling rack. The grid should be placed on a deep baking tray in order to collect the icing
- Pour the glaze in a thin stream on the surface of the center, starting from the center The sides should be coated with an even layer of icing. Let the excess icing drip down to the tray.