Make a flour mound on your mixing board and add the butter, at room temperature, in the middle. Mix the other ingredients in and make a ball, wrap it in film and put it in the refrigerator for half an hour.
Spread the dough out on a flour-dusted board, cut out many biscuits, and in half of them cut out a central opening. Cook in the oven at 180 °C until they are slightly golden. Assemble the two parts by spreading jam or hazelnut cream between the full disc and the disc with a hole in it. Then dust with castor sugar and... buon appetito!
Recipe from the Cavallino Bianco Hotel in Rumo.