Wash, top and tail the gooseberries, discarding any that are damaged. Place a saucer into the freezer.
Put the gooseberries and 150ml/5fl oz water into a large pan or preserving pan. Bring to the boil and simmer for about 10 minutes until the fruit is softened.
Stir in the sugar and cook over a low heat until the sugar has dissolved.
Increase the heat and boil rapidly for 8-10 minutes before testing to see if set.
To test whether the jam has set: take the saucer from the freezer and drop a small spoonful of jam on to it. Allow it to cool for a minute then push your finger through the jam – if it wrinkles it’s ready; if not, boil for a few more minutes. Continue testing until the jam is ready. (Always remove the jam from the heat while you’re testing so that if it’s ready you won’t overcook it.)
Meanwhile, sterilise the jam jars - first wash the jars in soapy water and rinse in clean warm water. Allow them to drip-dry, upside down, on a rack in the oven set to 140C/275F/Gas 1. Leave them there for at least half an hour while you make the jam.
Once the jam is ready, turn off the heat, skim off any scum and leave to stand for 15-20 minutes.
Spoon the jam into clean sterilised jars and seal tightly with screw top lids while the jam is hot.