Ingredients

• 100g plain flour
• 35g cocoa powder
• 1 tsp baking powder
• ¼ tsp salt
• 3 eggs at room temperature
• 3 egg yolks at room temperature
• 170g sugar
• 1 tsp vanilla extract
• 30g butter
• 60ml milk

Preparations

step 1

Line the base of a greased 23-centimetre cake tin with baking paper. Preheat oven to 175C.

step 2

Sift flour, cocoa, baking powder and salt together. Whip eggs, yolks and sugar on high in the bowl of a stand mixer until ribbons form and the volume has nearly tripled. Add vanilla when nearly there.

step 3

Heat the milk and butter until hot but not boiling and set aside. In three increments, fold the sifted dry ingredients into the egg mixture by hand, using a spatula and holding the bowl at an angle towards you. Gently fold from the centre of the bowl down to the base and scrape from the edge to the top of the bowl and back to the centre. Repeat this a few times until the dry ingredients are mixing in and there are no pockets of flour.

step 4

After the second increment, add a bit of the hot milk and butter mix and fold in. This activates the baking powder so the mix will puff up again. Then fold in the last of the dry ingredients and the remaining milk mixture. Fold again and immediately pour into prepared tin.

step 5

Bake for 30 minutes until puffed and springy when touched. Allow to cool in the tin and then flip it out. You should be able to slice this cake into three thin rounds. If you prefer to do two layers only, slice it in half horizontally.