Make the sponge

• Preheat the oven to 180°C and grease and line two round cake pans.
• Beat the softened butter with the caster sugar until pale and fluffy.
• Add the eggs one at a time, beating well after each addition.
• Mix in the vanilla extract and milk.
• Fold in the sifted self-raising flour and baking powder until just combined.

Bake the cakes

• Divide the batter evenly between the prepared pans and level the tops.
• Bake until golden and a skewer comes out clean.
• Leave to cool in the pans for 10 minutes, then turn out onto a cooling rack to cool completely.

Make the buttercream

• Beat the softened butter until smooth and creamy.
• Gradually add the sifted icing sugar and beat until light and fluffy.
• Mix in the vanilla extract.
• Divide the buttercream and tint one part yellow and a smaller part brown with gel colouring.

Fill and crumb coat

• Level the cooled cakes and place the first layer on a cake board.
• Spread a layer of buttercream over the top and place the second cake layer on top.
• Cover the whole cake with a thin crumb coat of buttercream and smooth it with a spatula.
• Chill until the crumb coat is firm.

Create the sunflower petals

• Load a palette knife with yellow buttercream.
• Press and drag the palette knife around the sides and top of the cake to form petal shapes, overlapping them as you go.
• Continue all the way around until the flower is complete.

Add the centre

• Fill the middle of the flower with brown buttercream using the palette knife.
• Texture the brown centre with small dabs to mimic sunflower seeds.
• Chill the cake to set the buttercream before serving.