Beat the egg whites with the sugar, vanilla sugar and a pinch of salt until stiff. Gently fold the egg yolk into the snow. Now gradually stir in the flour and the melted margarine.
Line a baking tray with baking paper and spread the sponge mixture on it. Bake in the preheated oven at about 200 °C for about 10-12 minutes.
For the strawberry cream, soak the gelatine in cold water, then wash and chop the strawberries for the filling and mix with Grand Manier and sugar. Blend with a hand blender until only small pieces of strawberries are visible. Mix the mixture with the curd cheese and the whipped cream.
Heat the orange juice and dissolve the soaked gelatine in it. Stir the gelatine into the strawberry mixture.
Cut out the base for a small tart pan from the sponge dough, spread with strawberry jam and place the dough in the tart pan. Cut the remaining sponge dough into sheets and line the edge with them. Or line with sponge cake.
Pour the strawberry mixture into the tart mold and let it cool for at least an hour until the strawberry cream has set.
Then wash and chop the remaining strawberries and arrange them in a circle in the center on top of the jellied strawberry cream.
Cover with cake jelly according to package instructions.
Shortly before serving, decorate the outer edge of the cake with whipped cream.