• Preheat oven to 180 degrees celsius (fan-forced) and line and grease 2 X 20cm round cake tins.
• Place the egg whites into the bowl of an electric mixer and mix on a high speed until white and fluffy.
• Reduce the speed to medium and add the caster sugar, 1 teaspoon at at time. This will take 3 - 4 minutes.
• Reduce the speed to low and add the egg yolks.
• Turn the mixer off and carefully scrape down the sides. Sift the cornflour, bicarbonate of soda, cream of tartar over the egg white mixture. Add the vanilla and water and mix on a medium/low speed until just combined.
• Divide the mixture between the greased cake tins and bake for 20 - 25 minutes or until golden and cooked when tested with a skewer.
• Leave the cakes in the tins for 5 minutes and then place onto a wire rack to cool completely.

Thermomix Instructions

• Preheat oven to 180 degrees celsius (fan-forced) and line and grease 2 X 20cm round cake tins.
• Place the bicarb soda, cream of tartar and cornflour into Thermomix bowl and mix for 10 seconds, speed 5. Set aside until needed.
• Wash and dry the Thermomix bowl - this is very important!
• Insert the butterfly attachment into the bowl. Add the egg whites and mix for 2 - 3 minutes on speed 3 or until the egg whites are stiff.
• Set the Thermomix to speed 3 and remove the measuring cup. Add the caster sugar to the bowl one spoonful at a time. Please note this will take up to 5 minutes.
• With the measuring cup still off, set the Thermoix to speed 1 and add egg yolks one at a time.
• Scrape down the sides of the bowl and remove the butterfly attachment. Add the vanilla extract, hot water and cornflour mixture prepared earlier to Thermomix bowl. Mix for 5 seconds, speed 3.
• Again scrape down the sides of the bowl and mix for 4 seconds, speed 3.
• Evenly divide the batter between the two prepared cake tins. Bake for 20-25 minutes or until the cakes are golden and a skewer comes out clean when inserted in the middle.
• Allow the sponges to cool for 10 minutes before carefully transferring to a wire rack to cool completely.

To decorate

• Combine the thickened cream and icing sugar in a bowl and use an electric mixer to mix until soft peaks form.
• Spread the jam over the top of one of the cakes. Add half of the whipped cream.
• Place the second cake on top and spread the remaining whipped cream over the top of the cake.
• Decorate with fresh strawberries and refrigerate until needed.