I have been playing with my Sunshine bitters quite a bit recently so I though I would post the recipe since it is so simple.
Take a bottle .750 of a clean vodka. More expensive is not always better, I use Square One, but anything you wouldn't be afraid to drink is fine. Infuse a 2 ounce jigger full of Cardamon pods in the bottle for a full week. (a bit longer for a full liter bottle). Then add a single ounce jigger full of Saffron and infuse that for 2 days or until the threads look bleached. Strain and rebottle. While I developed this for a Sherry based cocktail, it seems to work very well with most clear spirit drinks.