The Catherine Sponge

Another Gluten-free cooking for kids recipe

Here's a recipe for The Catherine Sponge which I developed a few weeks ago in honour of our soon to be Princess Kate Middleton.  Don't be put off by the length of the recipe or the long list of ingredients.  It's actually quite quick to make and I promise you it's worth the effort.  Certainly a good recipe to impress your guests during the Royal Wedding and the perfect cake for all those street parties takng place around the country.

For the full story on the making of The Catherine Sponge see


Serves 8

Preparation time

Cake: 35 minutes Filling: 25 minutes Passion Curd: 15-20 minutes


150ml Champagne (or a Sparkling Wine like Cava or Prosecco)
1 Vanilla pod
300g unsalted butter at room temperature
350g caster sugar plus 1 tbs (to be used in the Champagne reduction)
6 eggs
200g gluten free flour
100g ground almonds
1 tsp salt
230g caster sugar
115ml Champagne (or a Sparkling Wine, like Cava or Prosecco)
1/8 tsp cream of tartar
3 egg whites
Pinch of sea salt
55g (about 8 large) white marshmallows*
2 tbs milk
3 tbs passion fruit juice (you will need abot 4 passion fruits)
3 egg yolks
80g caster sugar
50ml passion fruit juice
35g unsalted butter


Catherine Sponge

Preheat oven to 180 C (170 C fan oven) or gas mark 5.  Prepare two round baking tins (8 inch/20.5 cm diameter) by greasing with a little butter and lining the bottoms with greaseproof paper.  Dust with a little flour being sure to remove any excess flour.  

Place the Champagne,  1 tablespoon of sugar and vanilla pod in a small saucepan and slowly bring to boil, swirling the pan to make sure the sugar dissolves.  Once the sugar has dissolved, bring  the mixture to boil and simmer over low heat until the liquid is reduced to about 3 tbs. Leave to cool while you make the cake.

Sift the flour, baking powder and salt into a bowl.  Add the ground almonds and stir through gently to combine. Beat the butter and sugar in a large bowl until light and fluffy.  Add the eggs a little at a time, beating well with each addition.  The mixture should resemble mayonnaise.  Using a large metal spoon add the flour and almond mixture and combining gently.  Do not overmix.  Add the Champagne reduction and mix through.  Gently pour the mixture into the prepared pans. 

Bake for about 20- 25 minutes until the cake is lightly golden and just set.  Allow to cool on a wire rack for a few minutes.  Run a clean palette knife around the edges and invert the tin.  The cake should release from the tin easily.  Leave to cool completely before assembling.

Passion Fruit Marshmallow Filling

In a small saucepan combine the marshmallows and milk and heat gently, stirring the mixture until the marshmallows are melted. Once melted add the passion fruit juice and stir through.

In a heavy saucepan, combine the sugar, cream of tartar and Champagne.  Swirl gently to dissolve the sugar over medium heat.  Once the sugar is dissolved you can boil the mixture until it reaches soft ball (240 C) on a thermometer.  

Whilst the sugar is boiling, beat the egg whites with a pinch of salt until they form stiff peaks.   When the sugar syrup has reached the correct temperature, add the marshmallow mixture and stir through until combined. Put the mixture back on the heat and boil rapidly until it reaches 240 C (soft ball) again.  Transfer the sugar mixture into a pouring jug. 

  Place the electric hand whisk in the stiff egg whites and switch on to medium power.  Steadily and slowly pour in the syrup. The mixture should go soft, glossy and billowy.  Avoid pouring the syrup on the beaters as this will harden the syrup and make the filling go grainy.  If the mixture becomes too stiff, just add a little hot water, no more than a teaspoon at a time. 

  *Note on Marshmallows:  If possible avoid the little marshmallows which are used for decorating cakes and biscuits.  

  Passion Fruit Curd

Strain the egg yolks into a bowl.  Add the sugar and the passion fruit juice.  Mix well.   Pour this into a medium saucepan and cook over a low heat, stirring continuously until the mixture thickens and coats the back of a spoon.  The amount of cooking time will depend on the type of saucepan used so allow anywhere from 5- 15 minutes.  Do not allow the mixture to boil or it will be ruined.  When the mixture is thick enough, remove from the heat and whisk in the butter a little at a time.  Refrigerate for one-two hours before decorating cake

To assemble the cake

Spread a layer of the passion fruit curd on top of one of the sponges.  Leave the curd to set for about 15 minutes.  Then add a  layer of marshmallow filling on top of the curd.  Sandwich together with the second sponge.  Finish with a dusting of icing sugar on top