6 cups unchlorinated* water
1¼ cup coarse kosher salt (1 cup if using fine sea salt)
2 heads napa cabbage, cut into 1-inch pieces
½-1 cup gochugaru** (Korean chili pepper powder; adjust to suit your desired heat level)
1 daikon radish, cut into bite-sized pieces
6 scallions, greens included, roughly chopped
1 head of garlic, bulbs separated, peeled and minced
1 tablespoon fresh ginger, minced
4 tablespoons fish sauce
1 tablespoon sugar
Combine salt and water in a large bowl, stirring to dissolve. Add the cabbage pieces and toss well. Weigh down cabbage with a plate if needed to keep it beneath the surface of the brine, and let stand at room temperature for 4-8 hours, or until the cabbage softens.
Drain the cabbage, reserving a cup of brine.
In a large bowl, combine the remaining ingredients and mix thoroughly. Add the cabbage and mix well by hand, massaging as you go. Feel free to enjoy some of your kimchi now, before fermentation.
Transfer the remaining mixture into four quart-sized glass jars, packing it in firmly as you do so. (A Vitamix plunger, straight rolling pin, or back of a flat-ish spoon will help.) You want to remove any air pockets and leave 2-3 inches of head space in each jar.
Swirl the reserved brine around the bowl and use it to top up any jars where the vegetables are not fully submerged, then seal the jars tightly.
Rest at room temperature, away from direct light, for about 3 days. Fermentation is temperature-dependent, so it may take more/fewer days if your kitchen is especially cool or warm. Place on a tray or baking sheet to catch any spills. (The vegetables will release more liquid as they ferment.) Check your kimchi each day, removing the lid to allow excess carbon dioxide to escape, repressing the vegetables under the surface of the brine if necessary, and tasting for doneness. You want a bit of tang, but don't want the fermentation to turn the vegetables too soft. When it's deemed ready, put it in the fridge and eat within six months.
*Chlorine will impede the microbial activity needed for fermentation. Some water filters will remove chlorine, or you can set out a pitcher overnight or boil for 20 minutes, then cool (as hot water will also kill off the good bacteria.)
** You might experiment with the heat and start with a ½ cup and work your way up to 1 cup of gochugaru.
Makes about 4 quart-sized jars