Preheat oven to 160 °C (320°F) with the fan on and line the bottom of two 8x3 inch baking tins with baking paper without greasing the bottom. Leave the sides of the cake tins ungreased and bare.

In a bowl combine your flour, cornstarch, baking powder and salt. Mix until well combined. Set aside.

In a medium sized bowl add in the egg whites and white vinegar, and using a hand or stand mixer, whip on a medium high speed for 30 seconds until foamy. Gradually add in ⅓ cup of the sugar and then continue mixing for a further 2 minutes. Then turn your mixer down to low and mix for a further minute. You should end up with stiff peaks. Set aside.

In a large bowl add in your remaining ⅓ cup of white sugar and warm water. Mix so that the sugar is coated in the water. Add in the egg yolks and vanilla, and with a hand or stand mixer, whip on a medium high speed for 4 minutes, and then turn the mixer down to low and mix for a further minute. Your mixture should now be thick and you should be able to create ribbons with it when you lift it up with a spoon.

Stream the vegetable oil into the egg yolk mixture while mixing on a medium speed. Mix until well combined.

Add in half of your egg whites to your egg yolk mixture, and using a spatula gently fold together until just combined. Then sift in your dry ingredients, and gently fold through until just combined. Finish off by adding in the remaining egg whites and gently fold until just combined.

Distribute the batter into your baking tins and then tap your baking tins lightly on your counter. Then run a thin knife or toothpick through the batter to remove any large air bubbles and then bake for 25 minutes.

Once the sponges are done, immediately tap them on the counter from a height of about 10cm, and lay them upside down (while still in their baking tins) on a wire rack to completely cool.

Once cooled, run a thin knife around the edges to release the cakes from the cake tins, and then turn them out onto a wire rack.

Combine the sugar and hot water together for the simple syrup and mix until the sugar is completely dissolved. Using a pastry brush, generously brush the top and sides of the sponges with the simple syrup.

In a large bowl add in the whipped cream, icing sugar and vanilla. Whip until you reach stiff peaks.

Place one sponge cake layer down, and cover the top with a thin layer of raspberry jam filling. Place strawberries on top. Cover with a generous amount of whipped cream and spread it out evenly.

Place your next sponge cake layer on top and then cover with more whipped cream. Finish decorating with more strawberries on top.