Beat the mascarpone and caramelized milk with a mixer. Separately, beat the confectionery cream and then gradually add it to the mixture.
Put 2/5 cup (100 g) finely ground walnuts and stir well with a spatula. Put some of the cream in a form with removable sides.
Continue with a row of biscuits, cream and so on until out of ingredients. Be sure to dip the biscuits for a second in the milk or coffee when arranging them.
Return to the fridge for at least 7 hours, then take the cake out of the form. Put the rest of the walnuts along its sides.
I had a bit of a dried out chocolate cake that I crumbled and sprinkled on top of the cake.