Sponge: Mix all ingredients with a paddle for 5-7 minutes at medium speed. Scale up 400 g in a 18 cm round silicon mould and bake for 50 minutes at 145 degrees.
Filling: Warm up Creme Fraiche and fold in White Truffel carefully.
Cut the sponge horizontally in three layers. Pipe 3 rings of the Creme Fraiche filling and pipe Les Fruits in between. Repeat with the other layer. Spread the filling evenly around the gateau and finish with some Les Fruits on the top.