Preheat the oven to 180 degrees Celsius (350 Fahrenheit).
To make the sponge, use a hand mixer to beat together the sugar and butter until you get a creamy texture.
Add the eggs one by one beating well after each addition.
Sift in the flour, add the vanilla extract and mix well to get a thick batter.
Grease and flour 2 round cake tins ( mine are 7.5 inches or 19 cm in diameter), and divide the batter evenly between the 2 tins.
Bake for 25 minutes until the sponges are golden and a skewer inserted in the middle comes out clean.
Remove the sponges from the oven and leave them to cool down completely.
To make the buttercream, add the sifted icing sugar, vanilla extract, soften butter and milk to a food processor, and whizz until smooth.
If the sponges have a slight dome, you can use a sharp knife to cut off the top and have a flat sponge, which will help with even layers.
Place the first sponge on a plate or cake stand, spread a third of the cream over, top with the second sponge, spread another third of buttercream, then use the remaining cream to add the finishing touches to the sides.
Decorate the cake with strawberries and blueberries.