1) Prepare the brownie: chop the chocolate and let it melt in a bain-marie. Add the soft butter into small pieces and let it melt slowly, continuing to mix with a whisk; remove from the water bath and let it cool completely. Mounted with whisk the eggs and sugar until the mixture is light and fluffy. Incorporate the mixture into the melted chocolate pouring it slowly and continuing to mix, then also mix the sifted flour with the cocoa powder and a pinch of salt.Pour the mixture in a 15×15 cm square mold lined with a sheet of baking paper forming a uniform layer and bake in the oven at 180 ° for 25 minutes. Turn out the sweet, let it cool, then cut it into cubes.
2) For the chocolate cream: you work egg yolks with sugar, incorporated the cornstarch, stirring with a whisk to avoid the formation of lumps, then add the boiling milk, a little at a time; transfer to a very low heat and cook until the cream has thickened. In the end incorporated finely chopped milk chocolate and stir until melted. Transfer the cream in a bowl, cover it with plastic wrap to prevent the crust from forming on the surface e leave it to cool completely on a cold water bath.
3) Meanwhile prepared the zabaglione cream. Gather the egg yolks and sugar in a saucepan e get started whisk until the mixture is swollen and clear. Transfer over very low heat and add the Marsala slowly, continuing to mix with a whisk; let it cool down. Mounted cold cream with whips and stir in the prepared zabaglione, stirring with a spatula with gentle movements from the bottom up to avoid disassembling the mixture.