Prepare a batch of brine and place into a large non-reactive bowl.
Add vegetables; mix well. Cover with a large plate or a sealed plastic bag half-filled with water to keep vegetables submerged; stand overnight.
Rinse and drain vegies.
Place vegetables, vinegar, sugar and spices into the Thermomix bowl and cook 10 min/100°C/Reverse/speed soft/spatter guard in place.
Make a slurry with the cornflour and water and add to the mixture in the Thermomix bowl. Cook 5 min/100°C/Reverse/speed soft.
Spoon hot pickle into hot sterilised jars; seal immediately. Label and date jars when cold. Leave in a dark cool cupboard for around 3 weeks before transferring to the fridge and using.