- 900g strawberries
- ½ lemon, juice of
- 1kg jam sugar
Pre-heat the oven to 140C/120C Fan/Gas 1. Chill three small plates in the freezer (this is to test for setting later on). Line a baking tray with double-thickness kitchen paper. Wash 4-6 jam jars and rinse in hot water. Put them upside down on the tray and put in the oven to sterilise while you make the jam (or in the dishwasher on a hot cycle).
Halve 900g strawberries. Put them in a very large saucepan with the juice of 1⁄2 lemon and 1kg jam sugar. Heat gently until there are no sugar crystals left. Stir gently as it heats, but take care not to damage the strawberries.
When the sugar has dissolved completely, bring to the boil and boil rapidly for 4-8 minutes or until setting point is reached.
Test for setting by adding a spoonfull of jam to a cold plate. If it wrinkles the jam is ready.
Remove any scum from the surface with a large spoon, then set aside for 15 minutes.
Fill the warm jars with the jam, making sure it comes to the top. Immediately put a disc of waxed paper (from a pack of jam pot covers) on top, wax-side down. Cover with cellophane, secured with a rubber band or lid, and label the jar.
Unopened, the jam will keep for 12 months.