Basic Sponge Cake

Preheat the oven to 350°F (175°C) and grease a round cake tin with margarine or cooking spray.

Whisk the egg whites in a clean, dry bowl until stiff peaks form, then set aside.

In a separate bowl, beat the egg yolks with the caster sugar until pale and creamy, about 3-4 minutes.

Sift the self-raising flour and salt together into the egg yolk mixture, then fold gently with a spatula until just combined.

Pour the melted margarine and hot water into the batter, stirring until the mixture becomes smooth and pourable.

Gently fold the whisked egg whites into the batter in two additions, being careful not to deflate them completely.

Pour the batter into the prepared tin and smooth the top with a spatula.

Bake in the preheated oven for 30-35 minutes until golden brown and a skewer inserted into the center comes out clean.

Remove from the oven and allow the cake to cool in the tin for 5 minutes before turning out onto a wire rack to cool completely.