Rinse and trim the garlic chives, cutting them into 2-inch lengths. Peel and julienne the Korean radish and carrot. Thinly slice the garlic cloves.

Sprinkle Korean chili flakes over the prepared vegetables and toss to coat evenly.

In a medium saucepan, combine rice vinegar, water, sugar, salt, and fish sauce. Heat until the sugar and salt dissolve, then let cool.

Pack the chili-seasoned vegetables into a clean glass jar, tamping them down gently.

Pour the cooled brine over the vegetables, ensuring they are fully submerged.

Seal the jar tightly and refrigerate for at least 24 hours before serving.