Preheat your oven to 175°C and grease two 20cm round cake pans.
In a large bowl, combine the flour, caster sugar, cocoa powder, baking powder, bicarbonate of soda, and salt.
In a separate bowl, mix together the eggs, buttermilk, vegetable oil, vanilla extract, and red food colouring.
Gradually add the dry ingredients to the wet mixture, stirring until just blended.
In a small bowl, mix the white wine vinegar and baking soda together, then quickly add to the batter and mix well.
Divide the batter equally between the prepared cake pans and smooth the tops.
Bake in the oven for 25-30 minutes or until a toothpick inserted into the centre comes out clean.
Allow the cakes to cool in the pans for 10 minutes, then transfer them to a wire rack to cool completely.
Instructions for the Cream Cheese Frosting:
In a large bowl, beat the butter and cream cheese together until creamy.
Gradually add the icing sugar and beat until combined.
Stir in the vanilla extract and 2-3 tablespoons of milk as needed to reach a spreadable consistency.
Instructions for Assembling the Cake:
Place one of the cooled cake layers on a serving plate or cake stand.
Cover the top with a generous amount of cream cheese frosting.
Place the second cake layer on top.
Spread the remaining frosting over the top and sides of the cake, creating a smooth surface.
Serve and enjoy your delicious two-layer red velvet cake!