*To toast & skin hazelnuts, put in one layer in preheated 180ºC oven for 10 to 15 minutes or until they are colored lightly and skins blistered. Wrap the nuts in a kitchen towel and let them steam for 1 minute. Rub the nuts in the towel to remove as much skin as possible and let them cool. In the bowl of an electric mixer fitted with the paddle attachment, blend the flour, the sugar, the baking soda, the baking powder, the salt, the cinnamon and the cloves until the mixture is combined well. In a small bowl whisk together the espresso, the milk, the yolk and the vanilla, adding the mixture to the flour mixture , beating until a dough is formed, and stir in the hazelnuts and chocolate chips. Turn out the dough onto a floured surface, knead it several times and halve it. Working on a large buttered and floured baking sheet, with floured hands, form each piece of dough into a flattish log 30 cm long by 5 cm wide and arrange the logs at least 8 cm apart on the sheet. Bake the logs in the middle of a preheated 180ºC oven for 35 minutes and let them cool on the baking sheet on a rack for about 10 minutes. Reduce the oven temperature to 150ºC . On a cutting board, cut the logs crosswise on the diagonal into 2 cm slices , arrange the biscotti, cut sides down, on the baking sheet, and bake them for 5 to 6 minutes on each side, or until they are pale golden. Transfer the biscotti to racks to cool and store them in airtight containers. MAKES: about 32 BISCOTTI ~-