Thinly slice the cucumber to a thickness of 2 mm slices. To remove some bitterness, you can brine the cucumber for 30 minutes. Combine the sliced cucumber and salt in a bowl, toss well then leave to stand for 30 minutes. Overwise, continue to the next step.
To make the pickling liquid, in a saucepan bring the sugar, coriander seeds, mustard seed,vinegar and water to a gentle simmer, for 2-3 minutes until the sugar is dissolved and the coriander seeds infused. Remove from the heat and then leave to cool
Remove any salt from the cucumbers and drain any excess liquid, then transfer to a bowl or jar and cover with the pickling mixture.
Cover and transfer to the fridge for at least three hours before serving, preferably overnight
