In a bowl mix the eggs with the flour being careful not to form lumps. While continuing to stir, add the milk and a pinch of salt. Let the batter stand for 15 minutes in Fresco® pre-cooled with the quick cooling function.
Heat a nonstick skillet well, pour in a ladleful of batter and cook the crepes one by one. When finished cooking, using a pastry cutter about 10 cm in diameter, cut circles out of each crespelle.
Peel the onion and slice it thinly, after which cook it in a pan with a drizzle of oil, a tablespoon of brown sugar, a few drops of balsamic vinegar, a pinch of salt and pepper. Add a glass of water so that it softens without drying out. Once cooked, quickly chill it in Fresco® with the quick chill function for 15 minutes.
Wash the radicchio, cut each clump into 4 wedges, season it with salt, pepper and a drizzle of oil, and cook it in an oven preheated to 180°C for about 15 minutes. Once cooked, quickly cool it in Fresco® with the quick chill function for 20 minutes.
Mix the ricotta cheese with a little oil and a grating of pepper to form a cream. With the help of a spoon spread some of the ricotta cream on top of a crepe disk, stuff with some radicchio and some caramelized onion, close with another crepe disk and repeat the operation so as to create another layer. Finish with the crepe disk, a layer of ricotta cream, some hazelnut crumbs and a tuft of caramelized onion. Grate the Asiago cheese on top of each crepe and cook them in the preheated oven at 180°C for 15-20 minutes.