• Grease and line a 22x12cm loaf tin with baking parchment. Preheat the oven to 165°C (325°F) fan/convection.

To Make the Vanilla Version

• In a measuring jug or the cup of a blender, blend together the caster sugar, vegetable oil, soy milk, vanilla extract, and white wine vinegar until smooth and slightly thickened.
  200 g caster sugar, 170 ml vegetable oil, 170 ml soy milk, 2 teaspoon vanilla extract, 1 teaspoon white wine vinegar
• In a large bowl, sift together the plain white flour, cake flour, baking powder, and fine sea salt.
  125 g plain white flour, 135 g cake flour, 1 teaspoon baking powder, ½ teaspoon fine sea salt
• Fold the wet ingredients into the dry ingredients until combined. Be careful not to overmix.

To Make the Lemon Version

• In a small bowl, place the caster sugar and the lemon zest. Rub together with your finger tips until fragrant.
  200 g caster sugar, zest of one unwaxed lemon
• In a measuring jug or the cup of a blender, blend together the lemon fragrant caster sugar, vegetable oil, soy milk, vanilla extract, lemon extract and lemon juice until smooth and slightly thickened.
  170 ml vegetable oil, 170 ml soy milk, 1 teaspoon vanilla extract, 1 teaspoon lemon extract, 1 tablespoon lemon juice
• In a large bowl, sift together the plain white flour, cake flour, baking powder, and fine sea salt.
  125 g plain white flour, 135 g cake flour, 1 teaspoon baking powder, ½ teaspoon fine sea salt
• Fold the wet ingredients into the dry ingredients until combined. Be careful not to overmix.

To Bake

• Pour the batter into the prepared loaf tin and smooth the top with a spatula. Cover the tin with a small baking sheet or a makeshift top from aluminum foil to prevent excessive browning.
• Bake in the preheated oven for 30 minutes. After 30 minutes, remove the cover and bake for an additional 30 minutes, or until a skewer inserted into the centre comes out clean.
• Remove the cake from the oven and allow it to cool in the tin for about 10 minutes. Transfer the cake to a wire rack to cool completely to room temperature.
• Once cooled, wrap the cake tightly in plastic wrap and leave overnight or for at least 4 hours before unwrapping and slicing.