Clean, wash and quarter the strawberries. Heat jam in a pot. Remove from the heat, add the strawberries and allow to cool.
In the meantime, separate 2 eggs, chill the egg whites. Cream fat, 150 g sugar, vanilla aroma and salt with the whisk of the hand mixer. Stir in egg yolks. Stir in 2 eggs and yoghurt one after the other.
Mix flour, starch and baking powder and finally fold in briefly.
Pour the dough into a greased box cake tin (approx. 12 x 22 cm) sprinkled with breadcrumbs. Remove approx. 6 tbsp. of the strawberry mixture and set aside. Pour the rest of the strawberry mixture onto the dough and swirl it loosely with a spoon.
Bake in the preheated oven (electric cooker: 175 °C/ circulating air: 150 °C/ gas: see manufacturer) for about 1 hour.
Take the cake out of the oven, immediately remove from the edge and let it cool on a cake rack for about 20 minutes. Then turn over and let it cool down for about 2 hours.
Beat the egg whites until stiff, then pour in 100 g of sugar. Lightly puree the strawberry mixture that has been removed, so that the mixture remains somewhat chunky. Remove 2 tbsp. with a few pieces and carefully fold into the beaten egg white.
Spread the beaten egg white loosely on the cake with a spoon. Brown lightly with a Créme-Brûlèe burner. Arrange the cake on a plate. Add the rest of the strawberry mixture.