Preheat your oven to 180°C (350°F). Grease two 8-inch cake tins with butter. Line the bottoms with parchment paper. This prevents sticking and makes the cakes easy to remove later.

Place softened butter and caster sugar into a large mixing bowl. Beat with an electric mixer for three minutes. The mixture should turn pale and fluffy. This step adds air and helps create a light sponge texture.

Add eggs one at a time. Beat well after each egg. This keeps the batter smooth and prevents curdling. If the mixture looks slightly split, add a spoon of flour and mix again.

In another bowl, sift the flour, cocoa powder, and baking powder. Sifting removes lumps and adds air. This helps the cake stay light and fluffy during baking.

Add the dry ingredients to the butter mixture slowly. Fold gently using a spatula. Pour in milk and vanilla extract. Mix until just smooth. Do not overmix the batter.

Divide the batter evenly between the two cake tins. Use a spatula to level the tops. This helps both cakes bake evenly and gives them a flat surface.

Place the tins in the preheated oven. Bake for about 22–25 minutes. The cakes should rise well and feel springy. Insert a toothpick in the center. It should come out clean.

Remove the cakes from the oven. Let them cool in the tins for 10 minutes. Then carefully transfer them to a cooling rack. Allow them to cool completely before adding filling.

Place butter in a bowl and beat until creamy. Add powdered sugar and cocoa powder slowly. Mix well. Add milk and vanilla extract. Beat until smooth and fluffy.

Place one sponge layer on a serving plate. Spread the chocolate buttercream evenly on top. Gently place the second cake layer over the filling.

Dust the top with powdered sugar or cocoa powder. You can also add chocolate shavings or fresh berries. Slice and serve your beautiful chocolate Victoria sponge.