Preparation 1. Place the kumquats, sugar, and spices if using in a non-reactive saucepan and let macerate for 15 minutes. 2. Add water and bring to a boil over high heat. Reduce heat to medium-low and simmer for 15-20 minutes or until the liquid has reduced and thickened (it will thicken more as it cools). 3. Place in an airtight container and store in a refrigerator. Use within two weeks. *I find the easiest way to chop kumquats is to cut off one of the ends so you can stand the kumquat upright and quarter it. The seeds are then easy to reach and dispose of.