1) Prepare the ganache. Finely chop the chocolate. Melt the butter with the grated zest of half a well-washed bergamot. Heat the cream until it almost boils; in a bowl pour it over the chocolate, adding the butter. Mix well so that all the chocolate melts (if it does not melt completely, spend a few minutes in a bain-marie).

2) Transfer the ganache to the refrigerator, stirring it from time to time until it starts to harden. Then put it in a pocket pastry chef with a 1cm smooth nozzle and form lots of piles the size of a walnut on a baking sheet lined with parchment paper.

3) Pass again in the fridge to firm up a bit, then quickly roll the truffles between your palms to round them. Put them in the fridge to firm up completely.

4) Sprinkle i truffles with a little powdered sugar, flavored with a pinch of bergamot peel remained grated. Keep in the fridge until ready to serve.