Step 1Remove the outer leaves of the napa cabbage and cut the cabbage into quarters lengthwise. Rinse the cabbage thoroughly between the leaves and dry the cabbage well.
Step 2Salt the cabbage, being sure to spread the salt evenly between the leaves. Place the salted cabbage in a plastic or non-reactive colander or strainer and place the colander over a bowl to collect any liquid. Set the cabbage aside for 30 minutes.
Step 3Meanwhile, combine the gochujang paste, chile flakes, water, vinegar, chopped garlic and grated ginger in a food processor, and pulse the ingredients to form a coarse paste.
Step 4Rinse the salted cabbage under cold running water, making sure to rinse the salt out from between each leaf. Dry the cabbage completely on clean towels. Cut each quarter crosswise into 2-inch to 3-inch strips, discarding the core. Place the cabbage in a glass or other non-reactive bowl and toss with the onion, radish and green onion.
Step 5Add the paste to the bowl, massaging it into the cabbage leaves and vegetables. Place the mixture into a deep non-reactive container (such as an 8-cup measuring cup), and weight the mixture down. Refrigerate 1 to 2 days before using to give the flavors time to ripen. This makes a scant quart of kimchi, which will keep for up to a week, refrigerated.
Step 1In a large bowl, whisk together the egg yolk, vinegar, water and 1/8 teaspoon salt until the yolks are velvety and a pale yellow. Very slowly, drizzle in the oil, whisking all the time, to emulsify and form a mayonnaise. Once all of the oil is added, stir in the garlic. Taste, and season with an additional 1/8 teaspoon salt, or as desired. This makes a generous 1 1/2 cups aioli.
Step 1Boil the eggs: Bring a large pot of water, along with the 2 tablespoons salt and the vinegar, to a boil over high heat. Carefully add the eggs. Cook the eggs for exactly 14 minutes, then drain and place the eggs in ice to cool immediately.
Step 2Once the eggs have cooled, carefully peel them. Using a length of thread or unflavored floss, halve the eggs lengthwise. Remove the cooked yolks (the yolks should be just cooked, with a bit of translucence at the center), and set aside. Clean the egg whites and refrigerate, covered, in a single layer.
Step 3In a food processor, combine the egg yolks, 1 1/4 cups aioli, gochujang paste, sesame oil and kimchi juice. Pulse until the ingredients are thoroughly incorporated and the mixture is smooth. Adjust the consistency as desired with additional aioli. Taste and adjust seasoning as desired with additional salt and pepper. This makes about 2 to 2 1/2 cups filling. Place the mixture in a piping bag.
Step 4Pipe the mixture into each of the egg white halves. Garnish the deviled eggs with a little chopped kimchi, a sprinkling of sesame seeds and slivered green onion. Serve immediately.