Begin by cutting up all of the peppers putting them in a bowl, put the cucumber in a separate one.
Coarsely chop the ginger, garlic, chili, coriander and the spring onion and place in a mini food processor and process finely.
If you don't have one, then finely chop them by hand.
In a small bowl add all the liquids, sesame oil, garlic, chili, ginger, black pepper and sugar in a bowl and stir to dissolve the sugar. Pour this over the chopped peppers and mix well.
Add 3 msk. (3 tbls.) of the lime juice and taste add the 4th if you want it a bit more tart. This can vary depending on the limes.
If you find that the sauce is too thick you can thin with a little water. It should just coat a spoon.
As the vegetables marinate they will release a bit of water to help thin the sauce a little more.
Let stand for 1/2 hour.
Just before serving add the chopped cucumber at the last minute.
Garnish with the green top of the spring onion sliced finely sliced on the diagonal and a little fresh coriander.