A short-ish season to enjoy the real deal Clementines doesn’t mean you have to do without…
as long as you plan ahead and make this very nice marmalade while the tasty little buggers are available in the market.
This recipe, based on one from the barefoot contessa, will yield a good dozen half pints of marmalade goodness – enough to see you through until real Clementines arrive from South America in July or so.
Note: by “real” Clementine, I mean actual, honest to da Google CLEMENTINES; not mandarin oranges or whatever other small, orange citrus fruit marketing folk are trying to pass off as the real deal. Tho’… truth be known, the imposters will work just about as well in this recipe.
INGREDIENTS
•24 Clementines
•2 lemons
•6 cups water
•4 cups sugar*
*Sound like a lot of sugar? I’ve cut it in half from the recipe it’s based on; so relax.
Wash the Clementines and lemons, then slice as thinly as possible (discard the ends) and toss in a large pot – my Dutch oven worked a treat.
Add the water, bring to a boil, stirring often, then remove from the heat, stir in the sugar, and set aside, covered, to rest overnight.
The next day, bring back to a boil, then reduce the heat to low and simmer, again stirring often, for two hours – yeh, I know it’s a long time, but some things are worth the wait.
Skim off any foam that gathers on the surface of the marmalade, then increase the heat to medium and gently cook the marmalade until it reaches 220º on a thermometer.
Full Disclosure: I don’t know if I have a bad thermometer or simple a cursed kitchen, but I have never had a jam or jelly reach the magic 220º. Fortunately, and since you are gently cooking the marmalade at this point; there are other ways to test that your project will jell 
properly once cooled: there’s The Spoon Test, a classic, or, you can place a tablespoon or so of your marmalade in a dish and pop it in the fridge for ten minutes or so. If it thickens, you’re good to go with processing your marmalade.
To preserve, fill prepared canning jars with the hot marmalade and process in a boiling water bath for ten minutes.
Remove the jars from the water bath and allow to cool on a rack – you should hear the lids “pop” telling you that they have sealed properly. Once the jars have cooled, test each lid to see that the little divot in the center of the top is pulled down – you have a properly sealed jar.
Enjoy your marmalade.