Asda galaxycake

Galaxy mirror glaze cake

A scrumptious chocolate sponge with fluffy vanilla buttercream decorated with a spectacular shiny glaze and glittering stars

By , 19 September 2017

(128 votes)

Galaxy mirror glaze cake
  • 3 Hours 30 Mins

  • Serves: 30

Mirror glaze tips:
The temperature of the glaze has to be just right. Too hot and it won’t be thick enough; too cool and it won’t flow over the cake.
Stir the ingredients for the glaze – don’t whisk as this will create air bubbles.
You can make the sponge and the glaze mixture up to 3 days ahead but you’ll need to apply the glaze on the day you’ll be serving the cake. Store the baked sponge in an airtight container and the glaze in the fridge.
To use glaze from the fridge, microwave for 10 seconds at a time until it’s just thin enough to pour.

Nutritional Info
Each 66g serving contains
  • Energy



  • Fat



  • Saturates



  • Sugars



  • Salt



of your reference intake.
Typical energy values per 100g: 1648kJ/394kcal.
  • 5tbsp golden syrup
  • 225ml sunflower oil
  • 225ml semi skimmed milk
  • 3 eggs
  • 256g self raising flour
  • 35g cocoa powder
  • 1½tsp baking powder
  • 225g light soft brown sugar
  • 75g caster sugar
  • 3 egg yolks
  • 225g unsalted butter, softened
  • 2tsp vanilla extract
  • 15g powdered gelatine
  • 200g granulated sugar
  • 200g glucose syrup
  • 150g sweetened condensed milk
  • 200g good-quality white chocolate, chopped
  • 3 different gel food colours
  • 20g white chocolate stars
  • Preheat the oven to 180C/ 160C Fan/Gas 4. Grease the inside of a 2L domed metal mixing bowl. Cut a 20cm circle of greaseproof paper, snip cuts into it like the spokes of a wheel, far enough in so the paper overlaps and sits snugly in the bowl. Use to line the base of the bowl.

  • Microwave the golden syrup for 3-5 secs until runny. In a separate bowl, beat together the oil, milk and eggs. In a third bowl, sift together the flour, cocoa and baking powder and stir in the sugar. Add the syrup and the milk mixture to the dry ingredients and beat into a thick batter. Pour into the lined metal bowl and bake for 1 hr 15 mins or until risen and a skewer inserted into the centre comes out clean. Cool completely on a wire rack.

  • To make the buttercream, gently heat the sugar with 3tbsp water in a pan until it dissolves. Boil until it reaches 110C on a sugar thermometer.

  • Beat the egg yolks with an electric hand-whisk while slowly pouring in the sugar syrup until thick, pale and mousse-like. Whisk in the butter, 1 cube at a time, then add the vanilla extract. Whisk until glossy and fluffy.

  • Slice the cake into 3 horizontal layers and sandwich together with half the buttercream. Thinly spread half the remaining buttercream over the cake, smoothing well. Chill in the fridge for 30 mins until set. Spread the remaining buttercream over the cake, smoothing well again. Chill for another 30 mins. Using a small spatula, smooth the icing one last time. Chill until ready to glaze.

  • To make the mirror glaze, soak the gelatine in 80ml cold water for 5 mins. Heat the sugar, glucose and 100ml water gently in a pan until the sugar dissolves. Bring to the boil until it reaches 103C. Remove from the heat. Add the soaked gelatine and stir until smooth. Stir in the condensed milk.

  • Put the white chocolate into a bowl. Pour over the warm condensed milk mixture and leave for 5 mins. Stir until smooth. Test the mixture with a sugar thermometer – when it cools to 30C it is ready to use. Stir occasionally as it cools to prevent a skin forming.

  • For a perfect finish, the glaze has to flow over the cake and drip off the bottom edge. For this, stand the cake on a plate smaller than its base, balance this on a small bowl, then put on a clingfilm-lined baking sheet.

  • Divide the glaze between three bowls. Stir gel food colour into each to make three different shades. Pour over the cake, alternating colours so they form flowing patterns and cover the buttercream. Any excess will drip off the base. Leave to set for 25 mins.

  • Lay the stars on baking paper. Once the glaze is set, arrange the stars on the cake. Transfer to a cake stand to serve.