Preheat oven at 160°C/320°F.

Separate the eggs in 2 large bowls.

In the yolk bowl, add sugar. Mix vigorously until creamy and pale.

Add in the oil, milk and vanilla. Mix vigorously until well combined.

Sift in the flour and salt batches. Whisk gently until combined, do not over mix.

Divide the batter into halves. In one of the halves, add cocoa powder. Mix until combined.

In the egg white bowl, add the cream of tartar. With an electric mixer, mix on low for few seconds until foamy. Add in the sugar in 3 batches. Continue mixing on high while adding the sugar until stiff peaks formed.

Fold half the egg whites into yellow batter. Fold until the whites disappear, do not over mix. Fold in the remaining whites into the chocolate batter. Fold until the whites disappear, do not over mix.

Transfer batter into a piping bag each.

In a 33x33cm pan, pipe the yellow and chocolate batter alternately and diagonally. Drop the pan on the table a few times.

Bake in preheated oven at 160°C/320°F for 15-18 minutes.

Remove the cake from the pan as soon as it’s out from the oven. Let it cool completely before cutting.

Trim the edges if necessary. Then cut 2 strips of about 6cm (height), or according to the height you desire. Use a 6-inch round ring to cut for the base. Place the 2 strips around the sides, and the round on the base. Cover to keep the cake moist, set aside.

In a bowl, add water and gelatines. Give it a quick stir and let it rest for 5 minutes to bloom.

Chop the chocolate and set aside.

In a small pot, add the yolks and sugar. Stir to combine. Gradually add the milk into the yolks.

Cook the mixture over a low heat for about 30 seconds. Do not boil or over cook the mixture. (prevent the eggs become scrambled egg) Remove from the heat before reaching the boiling stage.

Add the strained mixture into the chopped chocolate. Let it rest for 3-5 minutes before mixing it.

Mix until the mixture is well combined. Add in the melted gelatines (melted in the microwave). Mix until well combined. Set aside.

In a large bowl, add whipping cream and sugar. Mix on medium speed until soft peaks formed.

Add the chocolate mixture into the whipping cream in 2 batches. If you’re using an electric mixer, mix just a few seconds to combine. Add in the remaining chocolate mixture. Mix few seconds to combine. Switch to a spatula to scrape the bowl and to ensure even mixing.

Transfer the mousse into the prepared pan. Fill the pan all the way up.

Refrigerate for at least 6 hours or overnight.

With tip 353, pipe some deco and garnish with strawberry halves.

Cake is ready to serve.