Add the Prosecco and stir.

Then add the Tate & Lyle Jam Sugar and stir gently until dissolved completely.

Put a couple of small plates in the freezer ready for testing the setting of the jam.

Meanwhile, sterilise 9 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.

Increase the heat steadily to a rolling boil. After 15-20 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.

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. (Be patient, you may need to test it several times, as this testing is crucial to achieve the correct consistency).

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.

Seal with the lids and label. Store in a cool dark place.