Cover a baking tray of 22 cm diameter with baking paper, do not grease the sides. Preheat the oven to 180°C (top and bottom).
Beat egg whites to stiff foam, then gradually add sugar. Keep beating. The obtained foam should be thick, fluffy and shiny.
Still blending, start adding yolks one by one. Blend for about 8 more minutes.
Sieve the wheat and potato flour through a sieve together with the baking powder. Gradually add the mixture obtained to the beaten foam. Preferably, spoon after spoon, beating at low speed all the time. Do this very carefully. It is important to combine the flour with the resulting foam, but do not let it fall.
Put the prepared dough into the baking tray and put it into the oven for about 30 - 40 minutes.
Cool the baked sponge cake in the open oven. When cooled – cut it into three longitudinal parts of the same thickness.
Add the whipping cream, mascarpone cheese, vanilla beans and half lemon juice to the mixer bowl. Beat it to a stiff mass. Wash the strawberries under running water, then cut them into quarters and add to the cream together with the blueberries cut in half.
Remove TAGO Delice' meringue with strawberry flavour from the packet, put it on a board and cut it into four pieces, add to the strawberry-cream filling. Mix it carefully with spatula.
Place the sponge cake on a cake stand and place the first layer of cream on top of it, then place the second sponge cake and do this until the ingredients are exhausted. Grease the top of the dough with the cream and decorate with strawberries and meringue with strawberry cream from TAGO.