Add salt to the egg whites, add in half of the sugar in 2 batches, and use a handheld electric mixer to whip the egg whites until they form peaks and are glossy.

Add the remaining sugar to the egg yolks, and beat well until it turns pale and and thick. Add the rum raisins. The beaters of the mixer should leave a trail in the batter at this point.

Add the olive oil→rum raisin liquid→ and milk in that order, stirring well each time.

Add in 1/3 of the sifted cake flour from step 2, mix it in until blended. Add the remaining flour and fold it in using a cut-and-lift motion.

Using the same egg beater from step 6, stir in 1/3 of the beaten egg whites from step 3. Fold in the rest using a spatula.

Pour the batter into a lined cake sheet pan, and bake in an oven preheated to 180C for 14~15 minutes.

Remove the cake from the pan with the cooking sheet still intact, and let cool on a cooking rack etc.

When the cake has cooled down a little, cover it with another sheet of kitchen parchment paper and leave until it has cooled down completely.

While the cake is cooling, beat the ♥ ingredients together to make the filling.

Spread the cake with your favorite filling, and roll it up from the side (the shorter side) carefully.

Wrap it up in plastic wrap after rolling, and let sit in the fridge until the cream filling settles. Let it rest for 2 (if you are in a hurry) to 5 hours.

Decorate ithe cake in any way you like, and it is done.