Grease two, 8-inch sandwich cake layer pans and line them with baking parchment. Strain the self-rising flour and baking powder into a large mixing bowl, stirring in any bran remaining in the sieve. Stir in the superfine sugar.

Pour in the sunflower oil, water and vanilla extract. Mix well with a wooden spoon for about 1 minute until the mixture is smooth, then divide between the prepared pans. Bake in a preheated oven, 350°F, for about 25-30 minutes until the center springs back when lightly touched.

Leave the sponges to cool in the pans before turning out and transferring to a wire rack. To serve, remove the baking parchment and place one of the sponges on to a serving plate. Spread with the jam and place the other sponge on top. Dust the eggless sponge cake with a little superfine sugar before serving.

COOK'S TIP: This is a healthy variation of the classic Victorian sponge layer cake. It is suitable for vegans.