For the cake
250g plain flour
400g caster sugar
100g cocoa powder
1 tsp baking powder
1 tsp salt
2 tsp bicarbonate of soda
2 large free-range eggs
120ml Mrs Middleton's cold-pressed rapeseed oil
200ml hot water
1 tsp vanilla extract
A little melted butter for greasing the tins
For the icing
50g unsalted butter, softened
150g full fat cream cheese
300g icing sugar
1/2 tsp vanilla extract
250g fresh strawberries
Preheat the oven to 180°C (or 160°C for a fan assisted oven). Brush two 20cm cake tins with the melted butter and line them with baking parchment.
Put the eggs, buttermilk, oil and vanilla extract in a bowl or large jug and whisk lightly by hand.
Gently combine the dry ingredients (flour, sugar, cocoa powder, baking powder, salt and bicarbonate of soda) using the paddle attachment of an electric mixer.
Pour the egg mixture onto the dry ingredients, continuing to mix slowly, then add the hot water and mix until you have a smooth batter.
Pour half the batter into each tin and cook for 35 minutes.
Cool on a baking rack before icing.
To make the icing
Mix all the icing ingredients for several minutes with an electric mixer with paddle attachment, starting at a low speed and then increasing the speed until the icing is smooth and has increased in volume.
Place one cake layer upside down on a large plate and spread with half the icing. Add the second layer and top with the remaining icing and strawberries.