CAKE WITH LADY FINGERS AND CROISSANTS (NO BAKING)

I've made this cake so many times and in so many different variations, they're all good. This is the simplest recipe and the easiest one. Maybe you have made the recipe and you will only use the decoration idea. I made it for my son after he got part in a chess competition. He's 8 years old.

Ingredients:

1 liter milk
1 vanilla pudding+sugar as given in the instructions
1 chocolate pudding +sugar as given in the instructions
200 g butter
100 g powdered sugar
100 g cooking chocolate (50 g white and 50 g dark chocolate)
about 300 g lady finger biscuits (average 30 pieces)
1 large package of small croissants (17-20) or several big ones
1 whipping cream (for decoration)

Preparation:

First boil a liter of milk, divide it in half, in one half add vanilla pudding and sugar as instructed and in the other half chocolate pudding with sugar and mix well. In the end add 50 g white chocolate in the vanilla and 50 g of dark chocolate in the chocolate pudding and mix. Leave both to cool well.
Using a mixer mix aside 100 g of powdered sugar and 200 g butter until mixture is homogeneous. Add half in cooled vanilla pudding and the other half in the chocolate pudding and mix both well with a mixer.
Then line up biscuits previously soaked in milk as in image.
Put above them the white filling.
Then add the croissants previously soaked in milk.
Next add the white filling and finish with another row of biscuits soaked in milk.
Decorate with whipping cream or as desired.
Serve the next day.