Go Back
Print Recipe

Union Jack Cake

This cake uses a technique called 'biscuit joconde'. It's not as hard as it looks, and I hope I've explained it adequately. Below is a step by step how to make it. When you come to serve it, peel away the cake ring carefully. You should see your beautifully patterned Union Jack bavarois cake.
Course: Afternoon Tea, Cake, Teatime
Cuisine: British
Keyword: Coronation cake, Union Jack cake
Servings: 10

Equipment

  • Springform cake mould
  • Silpat

Ingredients

Ingredients for sponge:

  • 85 g ground almonds
  • 75 g icing sugar
  • 25 g plain flour
  • 3 large eggs
  • 3 large egg whites
  • 10 g caster sugar
  • 30 g unsalted butter melted

Ingredients for piping:

  • 200 g unsalted butter softened
  • 200 g icing sugar
  • 7 egg whites
  • 220 g plain flour
  • Food coloring in blue and red

Ingredients for the tricolour interior:

  • 1 barquette of raspberries
  • 1 barquette of blackberries
  • 500 ml double cream
  • 100 ml water
  • 12 g of gelatin sheets silver
  • 250 g caster sugar
  • Pinch of salt
  • A few drops of vanilla

To decorate:

  • raspberries, cherries or strawberries for the red
  • blackberries or blueberries for the blue

Instructions

Method for sponge:

  • Whisk the egg whites and white granulated sugar to firm, glossy peeks. Reserve in a separate clean bowl for later use.
  • Sieve ground almonds, icing sugar, plain flour together.
  • On medium speed, add the eggs a little at a time to the dry mixture until well combined.
  • Fold in one third whisked egg whites to your mixture to lighten the batter.
  • Then fold in the remaining whisked egg whites until just combined.
  • Add the melted butter.
  • Cover with cling film and keep the batter. We will use it later.

Method for the piping decoration:

  • Beat butter and sugar together until light and fluffy.
  • Gradually add egg whites. Beat continuously.
  • Fold in sieved flour.
  • Divide batter into two bowls. They will be red and blue.
  • Add the coloring until you get your desired shade.
  • Put the red and blue into separate piping bags.
  • Then, using a silpat (this is one of the things you really should buy, along with a digital thermometer and a decent peeler) placed on a flat baking tray (or turn it upside down), pipe out your Union Jack.
  • Once you have done your design, place the silpat in the freezer for half an hour.
  • I did this twice, in order to have enough length of pattern to circumnavigate the cake.

Method for the cake:

  • Preheat your oven to 250C.
  • Once your design is frozen, gently spread, using a spatula, the sponge batter over the frozen design in a long rectangular shape. It should be about 3mm thick.
  • Then bake quickly. It should only take about 15 minutes.
  • Prepare a rectangle (bigger than the cake) of greaseproof paper dusted with icing sugar.
  • After 5-10 minutes of cooling, no longer, flip over your sponge onto the icing sugar dusted paper. You will now see the pattern. Yay!
  • Using a ruler or a straight metal edge, cut, with a sharp knife, the sponge strip to the height of your bottomless cake mould (I used a springform ring). Straighten the edges too.
  • Place the cake ring on top of a flat sheet of greaseproof paper, and on top of that put a flat sheet of clingfilm.
  • Pull the clingfilm up tightly outside the cake ring.
  • Cut a length of greaseproof paper to fit the inside of the cake ring. It should be 1cm taller than the cake ring.
  • Carefully, taking your strip of patterned sponge, line the inside of your cake ring.
  • The pattern should be facing outwards, so that you can see it when you remove the ring. Use the second strip of patterned sponge, pressing the sides together, if one isn't big enough.
  • I cut strips of leftover sponge to fit the bottom.

Method for the tri-colour bavarois:

  • First rub the raspberries into a sieve. This is a bit of a pain and you could use raspberry jam but the acidity of fresh fruit is worth the effort. Keep pushing it through the sieve over a bowl. You'll end up with a lovely seed-free purée.
  • In a separate bowl, do the same with the blackberries.
  • Leave both bowls of fruit purée to the side.
  • Soak the gelatin sheets in cold water.
  • Combine the sugar and the water in a pan and heat until dissolved. Let it cool.
  • Squeeze out gelatin sheets, add to the sugar syrup.
  • Mix one third into the raspberry purée, one third into the blackberry purée.
  • Whisk the cream to soft peaks.
  • Mix one third of the cream into the raspberry purée and fold gently until combined.
  • Mix one third of the cream into the blackberry purée and fold gently until combined.
  • Into the last third of cream, add a few drops of vanilla. Into this also add the last third of gelatiney sugar syrup. Combine, gently.
  • Into your cake mould, pour the raspberry mixture.
  • Put it in the freezer for 15 minutes.
  • Then pour in the blackberry mixture.
  • Freeze for 15 minutes.
  • Cut the greaseproof paper inside the cake ring level with the top.
  • Lastly, pour in the vanilla mixture. Smooth it out nicely with a spatula.
  • Put the whole cake in the fridge. Allow to set for a few hours.
  • When you come to serve it, peel away the cake ring carefully. You should see your beautifully patterned Union Jack bavarois cake.
  • Decorate on top with a mix of raspberries and blackberries. You could also use cherries, strawberries and blueberries.