This is based on David Leibowitz's No Recipe Cherry Jam which he published in 2005. You can make smaller or larger quantities according to the fruit you have available. You'll need a large pan, a thermometer, glass preserve jars (such as Kilner or Parfait) and two plates to place in your freezer to help you test your jam. You can make apricot jam in the same way.
Author: Edinburgh Foody
Recipe type: Jam
Cuisine: British
Serves: 10
Ingredients
2 kg cherries
1200 gr sugar (approx)
Juice of 1 large lemon
Instructions
De-stalk and de-stone the cherries. Use a cherry stoner if you have one, it is so much quicker.
Weigh the cherries after you've done this task. You will need ¾ of this weight in sugar. Eg if you end up with 1600 gr cherries after you've taken out the stones, you will need 1200 gr sugar
Place two plates in your freezer. You'll use these to test that the jam has set.
Cut smaller cherries in half, larger ones in quarters or cut smaller if you prefer.
Place in your jam pan and very gently cook the cherries until soft,
Add the sugar and lemon juice and heat gently, stirring until the sugar has dissolved.
Bring to a rapid boil making sure you keep stirring so the jam does not catch on the bottom. Either clip your digital thermometer to the side of your pan or pop your conventional thermometer into the mixture to check that the mixture gets to the jam setting point 104C/220F.
You will need to continue cooking for 5-10 minutes.
Get one of the plates out of the freezer and place a teaspoon of the jam onto the plate and return to the freezer. If the jam is ready, it will wrinkle when you push it along with your finger.
If not, keep boiling for a further 5 minutes and test again.
Skim off any foam before placing in jars.
Recipe by Edinburgh Foody at http://www.edinburghfoody.com/2014/07/25/jams-to-remind-you-of-summer/