1. Cut napa cabbage into quarters then into 2-inch pieces. Toss with sea salt, massage for 2 minutes, and let sit for 1 to 2 hours until limp. Rinse 2 to 3 times under cold water and squeeze dry.

2. Whisk sweet rice flour and water in a saucepan over medium heat, stirring until thick and smooth, about 3 to 5 minutes. Cool to room temperature.

3. Combine cooled rice porridge, minced garlic, grated ginger, fish sauce, and sugar. Stir until smooth.

4. Add gochugaru to the aromatic base and stir until fully combined into a thick red paste.

5. Wearing gloves, add green onions and optional add-ins to the cabbage bowl. Spoon the paste over the top and massage into every leaf until uniformly coated.

6. Pack tightly into clean mason jars, pressing down until brine rises. Leave 1 inch of headspace. Seal loosely and ferment at room temperature for 1 to 5 days. Taste daily. When sour enough for your taste, seal tightly and refrigerate.