Step 1: Preheat the Oven

Preheat your oven to 180°C (350°F). Grease two 8-inch round cake tins and line the bottoms with parchment paper.

Step 2: Cream the Butter and Sugar

In a large mixing bowl, beat the softened butter and caster sugar together using an electric mixer or hand whisk until pale, light, and fluffy. This should take about 2-3 minutes.

Step 3: Add the Eggs

Beat the eggs in a small bowl, then gradually add them to the butter and sugar mixture, one at a time, beating well after each addition. If the mixture starts to curdle, add a tablespoon of the self-raising flour to bring it back together.

Step 4: Sift in the Flour

Sift the self-raising flour and baking powder into the bowl, and gently fold it into the batter using a spatula or wooden spoon. Add the vanilla extract (if using) at this stage. If the mixture is too thick, add 2-3 tablespoons of milk to loosen it slightly.

Step 5: Divide the Batter

Divide the batter evenly between the two prepared cake tins, smoothing the tops with a spatula.

Step 6: Bake the Cakes

Place the tins in the preheated oven and bake for 20-25 minutes, or until the cakes are golden brown and spring back when gently pressed in the center. A skewer inserted into the middle should come out clean.

Step 7: Cool the Cakes

Once baked, remove the cakes from the oven and let them cool in their tins for about 5 minutes. Then, turn them out onto a wire rack to cool completely.

Step 8: Fill and Assemble (Optional)

Once the cakes are completely cool, you can sandwich them together with your choice of filling. Spread buttercream, jam, or whipped cream on one of the cakes, then place the other cake on top. Dust with icing sugar for a classic finish.