When you have a glut of fruit, there's nothing better to do with it than to make jam. You might think making jam is difficult, but this recipe is actually really easy.
The quantities given are very approximate. You can adjust them according to how many cherries you have, and how many you have the patience to pit.
Prep your cherries
If your cherries have stems and stalks on, pull them off. Rinse the cherries thoroughly. Now remove the pips - I do this just by breaking the cherries apart with my thumb and kind of rubbing the pit out. Oh, and if you don't want to have red-stained fingers and nails for the next few days, wear latex gloves. So you know I said this recipe was easy? Well, it is. But this bit is deeply tedious and boring.
Start the jam
Put 2 or 3 small plates into your freezer - we'll be using these later to test whether the jam is ready. Hurl the cherries into a big pan. Add the juice and zest of one lemon - lemons contain pectin, which is the magical ingredient that causes jam to set. Heat the cherries on medium heat for 20-30 minutes until they have more or less disintegrated into pulp. You might want to mash them a bit to help the process along - it depends how authentically lumpy you want your jam.
Now you need to work out how much sugar to add. Pour your pulp out into a measuring jug or similar device. You'll need to add three-quarters of whatever the weight or volume of the fruit is. So if you have 2 cups of pulp, you want 1½ cups of sugar.
Finish the jam
Put the pan on the heat and stir the sugar until it melts. Increase the heat and bring the jam to the boil. It will bubble and spatter in quite a lively manner. Then it will start to calm down and thicken up. When you think it may be ready, place a teaspoon of the liquid on one of your chilled plates and put it back in the fridge for a minute or two. Take the jam from the heat just in case it is ready - you don't want to overcook it.
The jam is ready when your chilled sample forms a skin on top that wrinkles when you push it with your finger. Spoon your jam into sterilised jars.