1-Clean and cut the napa cabbage: Remove tough outer leaves, cut each head lengthwise into quarters with core attached, trim about an inch off the core end, rinse under cold water gently separating leaves, and shake off excess water.

2-Salt the napa cabbage: Place quarters in a large bowl, generously sprinkle 1/4 cup kosher salt per cabbage between every leaf focusing on thick stems, let sit 1.5–2 hours rotating every 30 minutes with a weight on top until stems bend easily and a rinsed leaf tastes seasoned.

3-Make the kimchi marinade: Cook 1.5 cups water and 1/3 cup rice flour over medium heat until thickened and translucent, then cool completely. Blend apple, onion, garlic, ginger, and fish sauce until smooth; add 1 cup gochugaru and pulse. Transfer to a large bowl, stir in the cooled paste and remaining gochugaru, then fold in julienned radish, carrot, and chives to form a thick red paste.

4-Rinse the napa cabbage: Rinse each quarter thoroughly under cold running water 2–3 times lifting leaves to remove salt, taste a stem piece (should be seasoned not briny), then gently squeeze out excess water without tearing.

5-Marinate the napa cabbage: Wearing gloves, spread marinade between every leaf coating both sides starting from outer leaves. Fold each quarter into a bundle, pack tightly into a sterilized jar leaving 1 inch headspace, and press down. Eat fresh or ferment at 60–70°F for 1–2 days before refrigerating.