- 15 large egg whites
- 2 1/2 tsp dr. oetker cream of tartar
- 375 g (8oz) caster sugar
- 250 g (5oz) plain flour
- 7.50 ml (1 ½ tsp) dr. oetker natural vanilla extract
- dr. oetker bright red, sky blue, lime green, and sunshine yellow gel food colours
- dr. oetker cake release spray
For the filling
- 175 g (6oz) unsalted butter, softened
- 325 g (11oz) plus 1 tsp icing sugar
- 5 ml (1 tsp) dr. oetker natural vanilla extract
- 100 g (3 1/2 oz) full fat cheese
- Preheat the oven to 180°C (160°C fan assisted oven/350°F/Gas 4). Spray five, 20cm (8inch) diameter Victoria sandwich tins with Cake Release Spray to grease.
- In a large, grease-free bowl, whisk the egg whites until stiff. Add the Cream of Tartar, half of the sugar and the Natural Vanilla Extract. Whisk until thick and glossy.
- Sift in the flour and remaining sugar into the mixture gradually, in 4 batches, folding in gently after each addition, until well combined.
- Divide the mixture equally between 5 bowls and add a few drops of a different Gel Food Colour to each bowl to achieve desired colour level. Carefully fold in the Gel Food Colour and spoon the mixture into the tins.
- Smooth the tops and bake on the middle shelf in the oven for 14-15 minutes until just firm to the touch and very lightly browned. Carefully turn on to a wire rack to cool completely.
- To serve, place the butter in a mixing bowl and gradually sieve and mix in all but 1 tsp icing sugar. Stir in the Natural Vanilla Extract and mix in the soft cheese. Mix well to make a smooth, creamy, spreadable filling. Spread 4 layers of sponge with sufficient filling to just cover and sandwich together. Serve dusted with remaining icing sugar.