These are my words of wisdom to you: Go make kumquat marmalade while you still can.
Get 1.5 lbs kumquats and slice them up thinly, reserving the seeds. Tie the seeds in a cheesecloth bag. Put the kumquat slices and the bag of seeds together in a non-reactive pot with 4 C water and cover it and let it sit for 24 hours.
The next day, put the pot on the stove and bring the mixture to a boil over moderate heat. Once it boils, reduce the heat to a simmer and let the mixture reduce down for 45 minutes to an hour, or until it has reduced down to about 4 C.
Once that’s done, 4 C sugar goes in with constant stirring, and everything cooks for another 15-20 minutes, or until it hits about 215-220 F and a teaspoon of mixture dropped onto a cold plate gels. Actually, you don’t even need a cold plate – just drip a bit onto a spoon and blow on it until it cools. It’s easy to see it gel that way, even.
Remove the bag of seeds at this point, and the marmalade is done. You can safely seal it in canning jars, freeze it, or keep it in the fridge.
This stuff is seriously simple and sublime. We made a batch using earl grey tea instead of water, too.