Preheat oven to 180 C / Gas 4. Grease 2 (15cm) cake tins and line with baking parchment.
In a bowl, with an electric handheld whisk beat the butter and sugar until fluffy. Add the eggs, one at a time, beating well after each addition. Sift the flour in gradually along with the vanilla extract until a smooth mixture forms. Distribute the cake mixture evenly between the two prepared cake tins.
Bake in the preheated oven for 30 to 40 minutes, or until a skewer inserted in the centre comes out clean. Remove from the oven and allow to cool in the tin for 5 minutes before transferring to a cooling rack. Allow the cakes to cool completely before filling and decorating.
For a larger cake:
You can use the same recipe unchanged for larger 25cm cake.