1. Put the strawberries, raspberries and blueberries in a large saucepan with the Tate & Lyle Jam Sugar and lemon juice. Leave to soak for approx 15-20 minutes, stirring occasionally with a wooden spoon and gently squashing the fruits. This will help the sugar to dissolve and draw the juices out. Put a couple of small plates in the freezer ready for testing the setting of the jam.
2. Place the saucepan over a low heat and warm gently until all the sugar has dissolved. Meanwhile, sterilise 8 x 200ml jars by washing them in hot soapy water, rinsing well, then place them in a low oven at 150°C/Fan 130°C/Gas Mark 2 for 15 minutes.
3. Increase the heat steadily to a rolling boil. After 10 minutes you can test to see if the setting point is ready. If you are using a Jam Thermometer then you can test it once the temperature reaches 105°C. To test the jam for its setting point, remove the saucepan from the heat and spoon a little jam onto a cold refrigerated plate and leave for a few seconds – it should wrinkle softly when you push your finger through it.
4. If the setting point has not been reached, return the saucepan to the heat and continue to boil for another 2-3 minutes. Then repeat the test again with a fresh refrigerated plate. (You may need to test it several times, be patient, as this testing is crucial to achieve the correct consistency).
5. Leave the jam to cool for about 10 minutes in the saucepan before skimming off any scum that rises to the surface and then stir well before pouring the jam into the warm sterilized jars.
6. Seal with the lids and label. Store in a cool dark place.

TIP: If you wash your fruit before adding to the pan, ensure it is dry, as wet fruit will aect the cooking and setting times.