If you haven't got homemade raspberry liqueur, you could either use store bought raspberry liqueur OR you could make some quickly in a sauce pan. I would recommend making your own as the store bought stuff will never taste as good! To do this I would add a bag of raspberries, 1 cup of sugar and 1/2 a 750 ml bottle of vodka to a saucepan. Heat it till it boils and all the sugar melts then let it cool slowly and the flavors meld together.