Plum and Elderberry Jam

I love the idea of cooking with ingredients that I've foraged for myself and managed to find both the plums and elderberries used in this recipe growing wild on common land not far from where I live (Richard Mabey's "Food for Free" is probably the best field guide on the subject - now in a handy pocket-sized edition - but for goodness' sake, do be especially careful about eating mushrooms that you come across!).  This recipe is from Fraser Doherty's "Super Jam Cookbook" (sounds like a nice lad, young Fraser -  a sort of teenage jam entrepreneur/geek) and makes me feel like Madame Cholet as I'm cooking it.  OK, she may not have been my favourite Womble (that's Orinoco) but I have to love someone who cooks Dandelion Stew and Bramble Jelly.

You will need several clean jam jars (the sort with metal lids - things like coffee jars with plastic lids are no good) with the labels soaked off and a packet of jam pot covers (available from hardware shops like Robert Dyas and kitchenware specialists like Lakeland).  Jam pot covers tend to come in two sizes (1 lb and 2 lb) - go for the larger ones if the jars you're using are wide-necked (as Bonne Maman ones tend to be).

Plum and Elderberry Jam (makes 3-4 1lb jars)

1kg granulated sugar
900g plums
100g elderberries
Juice of 1 lemon

1. Put a saucer or small plate into the fridge (you'll see why later).  Preheat the oven to its very lowest setting.  Pour the sugar into a baking tray/roasting tin and put it at the bottom of the oven to warm (hot sugar dissolves more quickly).  Put the clean jars (not the lids) on a baking tray on the shelf above.
2. Slit the plums and remove the stones but don't throw them away.  If the plums are large, you may need to chop them into chunks.  Put the plums, their stones (the stones contain a lot of pectin, which is what will help the jam to set), the elderberries and 1 tablespoon of lemon juice to start with into a large heavy saucepan.  Cook the fruit over a low heat for around 20 minutes until softened.
3. Add the warmed sugar to the fruit mixture and gradually bring it to the boil, stirring with a wooden spoon every so often.  Once the jam is boiling, keep it like that for around 5 minutes, making sure it doesn't boil over.  Keep stirring your jam to make sure it doesn't burn on the bottom - it should be starting to thicken.
4. You now need to keep checking your jam from time to time to see if it's starting to set.  Remove the pan from the heat and spoon a small blob on to your cold plate (remember that?). Leave the blob to cool and push it with the side of your finger.  If the sample wrinkles when you push it, it's ready.  If it's still too thin, add a little more lemon juice to the pan, return it to the heat and keep boiling and doing the cold plate test until it's ready.  Use a slotted spoon to fish out the plum stones.
5. Remove your hot clean jars from the oven and spoon or pour in the jam, filling them right up to the top.  A heatproof jug is very useful here, as is a specialist metal jam funnel.  Take care as hot jam is like molten lava and you can get a nasty burn if you're not careful.
6. In your pack of jam pot covers will be some discs of greaseproof paper.  Press one on the surface of each jar of jam (waxy side down), making sure that there are no gaps between the paper and the surface of the jam.  The pack will also contain cellophane discs.  Wet the centre of each one with a dab of water and place it (damp side up) over the jar of jam.  Secure in place with an elastic band - as the jam cools down, the cellophane disc will contract, forming an airtight seal.  Done properly, this will prevent mould forming on the jam and it will keep for at least a couple of years unopened.
7. Last but not least, sterilise the metal lids by putting them in a small pan of water and bringing to the boil before draining, thoroughly wiping dry and using to secure the jars.  Don't forget to label your jars with the contents and the date it was made.

Hubble bubble ...

The finished jam (named after the scrumping location)