These cakes are made with baking soda. Baking soda has become a staple in many households around the world. Not only can it be used for baking as here, but is also a great product to use to clean your home without resorting to using harsh chemicals. Check it out here:
Preparation: about 30 min.
Oven time: 15 minutes
Oven temperature: 200° C / 390° F
Middle shelf in the oven
The cake bottom can be frozen
3 tablespoons water
150 g [5,3 oz] sugar (1 2/3 dl / 0,3 pt)
2 tsp vanilla sugar
60 g [2 oz] potato starch (3/4 dl / 0,15 pt)
1 teaspoon baking powder
40 g [1,4 oz] cocoa (6-7 tablespoons)
3 dl [0,6 pt] light cream, 10%
4 egg yolks
90 g [3 oz] sugar (1 dl / 0,2 pt)
2 teaspoons of potato starch or corn flour
150 g [5,3 oz] unsalted butter
vanilla sugar / vanilla to taste
Filling and garnish:
1 can of pineapple, roughly chopped
1 small glass of cocktail berries
100 g [3,5 oz] roasted almond flakes
A few pistachio nuts
175 g [6 oz] melis (3 dl / 0,6 pt)
30 g [1 oz] cocoa (5 tablespoons)
30 g [1 oz] coconut fat, and if needed a little water
 Separate the eggs. Whisk egg whites and water completely stiff and whisk in sugar and vanilla sugar / vanilla. Beat the egg yolks lightly and add them and the dry ingredients that you have mixed and sifted beforehand.
 Cover a baking sheet with baking paper and spread the dough on it. Fry the cake bottom as indicated. Vault the cake bottom onto a grid and gently pull off the baking paper.
 Mix the cream, egg yolks, sugar and potato starch or corn flour in a saucepan and allow the mixture to thicken over low heat while stirring all the time. Cool the cream. Stir the butter white and work it into the cream, a little at the time, stirring heavily. Taste the cream with vanilla sugar.
 Let the chopped pineapple and cocktail berries drain off well. Cut the cake bottom into four equaly wide strips and place them on top of each other with butter cream, chopped pineapple and cocktail berries in between.
 Stir together an icing of melted, lightly chilled coconut fat, icing sugar, cocoa and if needed, a little hot water. Spread the icing on the top of the cake and sprinkle with chopped pistachios. Press roasted almond flakes along the sides of the cake. Cut the cake into 3-4 cm / 1–1,5 in wide bars and serve them well chilled.