You will need 3 half-pint glass food storage jars for this sauce.
     In a small bowl, stir together cocoa powder, sugar and brown sugar.
     In a medium heavy saucepan, combine whipping cream and butter. Cook and stir over low heat until butter is melted. Continue to cook and stir over medium heat about 3 more minutes until bubbly around the edge.
     Stir in sugar mixture. Cook and stir for 1-2 more minutes until sugar dissolves and the mixture is smooth and thick. Remove from heat.
     Add the chopped chocolate and raspberry liqueur. Stir until the chocolate is melted.
     Divide te sauce amongst the three jars. Seal the jars, decorate each with pretty fabric tied over the lid with ribbon (or however you wish to decorate the jars), and attach a card with directions for reheating the sauce. Store the sauce in the refrigerator for up to 1 week.
     To reheat the sauce, remove the lid from one jar. Put the jar in the microwave and heat on high power for 45 to 60 seconds, or until heated through. Remove jar from microwave and stir sauce. Or, empty the contents of one jar into a small saucepan and warm over low heat on the stove.
     Serve the warmed sauce over cake, ice cream, etc.
     Makes 3 jars (about 1 cup of sauce each).