Wash all vegetables and pre-measure all of your ingredients so you have them ready to go. Set aside a few large cabbage leaves [to be used at the end of the process].
Place the rest of the cabbage in a large bowl and sprinkle with sea salt. Toss to combine. Cover the bowl and allow its contents to sit at room temperature until the cabbage has wilted [expect this to take a minimum of one hour and as many as 12]. As it wilts, the cabbage will release around 1/4 cup of liquid.
While the cabbage is wilting, combine the garlic, ginger, chili pepper, carrots [if using] and apple or pear [or sugar, if using] in the food processor or blender until it forms a rough paste [around 30 seconds].
Now it's time to check on the cabbage- it should be wilted and there should be liquid in the bottom of the bowl. Remember, this could take as many as 12 hours, so give it time if it needs it!
Once the cabbage has wilted, drain and set the liquid aside. Pat the leaves dry. Thoroughly mix the cabbage with the paste. This is your basic kimchi mixture.
Pack the kimchi into 4 mason jars [try to avoid air pockets]. Add equal amounts of the liquid to each jar, making sure that each jar has at least an inch of headspace [if needed, add some water to the jars to make sure the kimchi is completely covered by liquid]. Press the mixture down firmly using a wooden spoon so that the brine covers the top.
Cover the top of each jar with one of the reserved large cabbage leaves. Seal the jars loosely. Let them sit at room temperature [65-75 degree Fahrenheit] for 3 to 5 days. Taste the kimchi every few days; it will be ready when it has developed a sour, spicy taste and a texture resembling that of sauerkraut. When the kimchi is ready, remove the big cabbage leaves from the top of each jar and store the jars [tightly sealed] in the fridge. The kimchi should keep for several months.