Bash 6 cardamom pods in a pestle and mortar until they split.
Melt the marmalade in a pan, then whisk in the vodka. Add the crushed pods. Don’t boil the mix, simply warm it for a few mins. Leave to infuse off the heat for 20 mins, then strain.
Add the Cointreau and lemon juice and chill (or keep in the freezer). Serve in glasses with a little more marmalade in the bottom, ice and a cardamom pod floating on top.