For the sponge cake roulade with mango whipped cream filling, first prepare the sponge cake batter. Beat the eggs with a mixer, one at a time, until foamy.
Sift in sugar and vanilla sugar and continue beating until sugar is dissolved. Mix flour, cornstarch, baking powder and 1 pinch of salt, sift and fold into the egg mixture with a whisk.
Spread the sponge mixture on a baking sheet lined with baking paper. Bake in a preheated oven at 180 degrees for 10 minutes until golden brown. Turn out onto a damp tea towel sprinkled with sugar and carefully roll up.
Let the sponge cake dough cool completely. Meanwhile, peel a ripe mango and dice it finely, keeping a few slices for decoration.
Whip the cream with cream stiffener, vanilla sugar and 1 tablespoon powdered sugar until stiff. Carefully fold in the mango cubes.
Roll back the sponge roll, spread with slightly warmed apricot jam, spread the mango filling on top, carefully roll up loosely and chill for 4 hours.