Melt white chocolate chips in a double boiler or a microwave until smooth, do not over cook it. Set the chocolate aside and allow to cool until just lukewarm.
Mix coffee or liquor with mascarpone cheese, taste and add more coffee if desire. *If your mascarpone is very stiff and thick, whisk it in small bowl until it is smooth and creamy.
When the chocolate has cooled a bit, whisk in the mascarpone until smooth then cover the bowl and place in the refrigerator overnight.
The next day: Grate the dark chocolate on the largest holes of your box grater. Toss the chocolate shavings with the cocoa.
Now scoop balls of the ganache with a spoon and roll quickly between your palms. If your hands get sticky dust them with powdered sugar. Roll the truffles in the shaved chocolate/cocoa mixture.
Keep the truffles in the refrigerator but it's important that you allow the chocolates to come to room temperature before serving.