Definitely serve this drink in small portions. Less is more as the saying goes, as this is a very indulgent treat. Think along the lines of espresso sized portions. A tea-cup or mug would be far too much in one sitting. To add cream or not to add cream, that is the question. Honestly, cioccolata calda is so rich, creamy and decadent that a swirl of cream on top just seems like overkill to me. That's just me though - you may feel differently. My preference is to serve this rich and thick Italian hot chocolate with a small spoon and some simple biscuits or wafers to dunk. Try biscotti, cantuccini or even some Viennese fingers.