In a saucepan, add 500 ml Water, 250 ml Pickle vinegar, 1 teaspoon Sea salt and 1 teaspoon Sugar. Bring to the boil and then leave to cool.
Put the radish slices into a large, airtight jar.
Pour in the cooled pickling liquid. Make sure to cover all of the radishes.
Close the lid and put into the refrigerator for at least 2 hours.
Notes
For some added spice, why not add some slices of jalapeno to the radishes?
If you like your pickles a little less tangy, then you can use less vinegar and more water. But you still need a good amount of vinegar to pickle them.
If you like sweeter pickles, then you can add more sugar.
Make sure to push all the radishes down in the jar once you have added the brine so that they are all submerged in the liquid.
Use a mandoline to slice your radishes super thin and make the process much quicker.