Remove any leftover stalks or soft blueberries and weigh out 900g of fresh blueberries and place them in the Instant Pot.
Place the Instant Pot on sauté and sauté the fresh blueberries with the white sugar and the juice of ½ a large lemon. Sauté until you see the colour from the blueberries staining the white sugar.
Turn off sauté, place the lid on the Instant Pot and set the valve to sealing.
Cook for 2 minutes on manual pressure.
Use NPR (natural pressure release) and remove the lid from the Instant Pot.
Drain the Instant Pot contents into a sieve and bowl. So that as you pour the blueberry jam into the sieve that any leftover liquid goes in the bowl beneath and you don’t lose the blueberry liquid.
Place the solids from the sieve back into the Instant Pot and place it back on sauté. Allow it to simmer for a couple of minutes and add in a little of the liquid back in a bit at a time.
Once it has simmered and you have a naturally thick blueberry jam, pour the jam into sterilised jam jars.
Place the lids on the blueberry jam jars once it is cool. Freeze once completely cold.