Start by chopping the head off the chilies and gently pressing down on them, scraping the seeds out.
Zest the citrus fruits carefully. Make sure you don’t end up getting some of the juice in as well.
Add them all to a mortar and pestle along with some salt.
Gently crush them until you get a slightly chunky paste.
Notes
While zesting, make sure you don’t end up adding the white pith, and use only the top layer. If you don’t have a mortar and pestle or just don’t want to use it for this recipe, you can pop everything in a food processor or blender and give it a quick blitz until it forms a paste. Make sure you de-seed the chilies before you use them for the recipe- this will help cut down the heat a little bit. Remember to choose ripe citrus fruits, ideally in their growing season. This will lend the Kosho the perfect flavor profile you’re looking for.