Trim the root ends and remove any tough outer layers.

Cut into small bite-sized pieces (about 1.5 cm).

Wash thoroughly to remove any dirt between the layers and drain well.

→ this helps them absorb seasoning evenly and prevents them from falling apart

Place the leeks in a bowl.

Add fish sauce and salt, and gently toss to coat.

Let sit for about 40 minutes, turning once halfway through.

Mix flour and water until smooth.

Cook over low heat, stirring continuously, until it slightly thickens.

Remove from heat and let cool completely.

Add gochugaru to the cooled slurry and let it bloom.

Mix in the blended apple, onion, and ginger.

Stir until you get a smooth, slightly thick paste.

Add the kimchi paste directly to the leeks, including all the brining liquid.

Gently mix until evenly coated.

Transfer to a container, pressing lightly as you fill it.

Fill only up to 80% to allow space for fermentation.

Add ½ cup water to the mixing bowl, swirl to collect remaining seasoning, and pour over the kimchi.

Leave at room temperature for 12–24 hours, until you notice gentle bubbles and a light tang.

Then move to the refrigerator to continue fermenting slowly.