Peel the daikon radish and carrot. Cut them into julienne strips, about 4-5 mm thick, so they maintain a good crunch. Slice the Thai chilis into small pieces.
Place the daikon and carrot strips in a mixing bowl. Sprinkle with 1 tablespoon of salt and toss until evenly coated. Allow the mixture to sit for 20 minutes, which helps draw out excess moisture, improving the pickles’ texture. Rinse the daikon and carrot thoroughly under cold water to remove the salt, then drain well.
In a pot, combine 250 mL water, 250 mL white vinegar, and 6 tablespoons sugar. Stir until the sugar is dissolved. Bring the mixture to a gentle boil, then turn off the heat and let it cool to room temperature.
In a clean, sterilized jar, layer the daikon and carrot strips along with the sliced Thai chilis. Pour the cooled vinegar mixture over the vegetables, ensuring they are fully submerged. Seal the jar tightly with a lid.
Let the jar sit at room temperature for about 3 hours to allow the flavours to develop, then transfer it to the refrigerator. The pickled carrots and daikon radish can be served after a few hours but will taste best after marinating for at least a day.
The pickles are now ready to serve! Use them as a side dish or add them to sandwiches, salads, or rice dishes for an extra burst of flavour. Refrigerate any leftovers; they will keep for up to a month when stored properly.