Add the orange jam. Divide the mixture into 2 and bake these 2 layers in a hot and oiled oven dish.
Make the cream by adding the diluted flour and sugar to the cooled milk. Stir nonstop on the stove until the cream thickens. Before you take it off the stove, add the yolks 1 by 1.
Assemble the cake by smearing the layers with cream on all sides and putting them on top of one another. Smear the entire cake with liquid chocolate. Garnish with grated white chocolate and walnuts.