To make the mixture of the cronuts put the flour in a bowl, make a hole in the center and add the yeast, sugar, vanilla and milk and start to knead.
Then add the egg, the butter cut into chunks and salt and knead until a smooth and homogeneous mixture is obtained. It will take about 10 minutes.

Form a ball then cover the bowl with some film and let the dough rise until doubled, it will take about 2 hours.Take back the dough and spread it on a floured work surface and with a rolling pin try to obtain a rectangle with a thickness of half a centimeter.
Make a cream by working the softened butter together with the flour and roll it over the rectangle of dough
Fold the dough into three, then roll it vertically with a rolling pin. Fold it again into three and let it rest in the fridge for about 30 minutes.
Take back the rectangle of dough and roll it out obtaining a thickness of about 2 cm. Then with two round cutters of two different sizes, made the donuts.
Place them on a baking sheet lined with parchment paper and let rise for 30 minutes.

Fry the ciambele peeled a little at a time in a saucepan with the boiling oil, turn them once golden and cook until you have a complete browning of all their surface.
With the help of a skimmer, then raise the donuts from the oil and place them on a plate lined with paper towels.
Prepare the icing to the water
Put the icing sugar in a small bowl.
Add lukewarm water and stir until a dense and homogeneous glaze is obtained.

Decorate the cronuts with the icing and then cover with colored sugar.

Serve your cronuts immediately.