Today is a great day to make Sour Cherry Jam

 We went to visit Rob and Jessie at their new "camp" on gorgeous Lake Champlain. The delicious local cherries were ready, and there was nothing that was going to hold me back from cooking a couple quarts of the sour ones I love best into a batch of Sour Cherry Jam. Do not be put off by the process, it really is simple (if time consuming). But worth it? YOU BET!
If you have never made jam before I suggest familiarizing yourself with the process. Here is a pretty good primer

First, wash and pit the cherries. This is infinitely easier with the use of a cherry pitter-- I highly recommend the old-fashion-y one I used, you can order it here.

 Chop the cherries fine, leaving a couple of whole ones for appearances, but not too many.  Put in a large pot with the zest and juice of a large lemon. The lemon will add pectin to the mixture. Pectin is what makes Jelly "jell". You can use commercial Pectin like Certo, but for a small batch, or for the cooking experience, try it this way for fun.

 Cook the chopped cherries with the lemon until very soft, about 20 minutes. Stir it every couple of minutes, don't let it burn on the bottom.

 This is what mine looked like when it was cooked. Carefully pour contents of your pot into a large measuring cup. Measure the amount of cooked fruit, and return it to the pot, with exactly 3/4 the amount of sugar. So, dear math majors, if you have 4 cups of cooked cherries, add 3 cups of sugar.  Put a couple of white plates into the freezer to chill, you will use these to test your jam's doneness.

 Continue cooking until the fruit-sugar mixture starts to gel and sheet off of the spoon, looking jammy, and thick. If foam forms, skim it off, and stir and stir, it would be a drag for it to burn at this point, wouldn't it?
When you think it's about jam, turn off the heat, and get one of the frozen plates. Spoon on a good dab, and return it to the freezer for a couple of minutes to chill. If you can push a line into it, and it doesn't run back together, "Its Jam". If it doesn't, cook it some more, and repeat.

Carefully spoon the hot jam into your adorable, warm, sterilized canning jars, wipe off any drips on the top, and top with the disk and loosely screw on the band.
Prepare a large pot of boiling water, with a rack or steamer basket, or just a couple of extra canning rings. Carefully lower the jars of jam into the boiling water and process for 10 minutes. Lift out, cool well.

If you are making a small amount of jam, (like one or two jars) and intend to finish eating it right away, you can just refrigerate it without bothering about the water bath, but do still sterilize the jars before.