Kimchi

So, this is how it works: you take some cabbage (or radishes, or cucumbers, or whatever vegetable is available,) throw it in a pot with some salt and water, and let it sit for a day. Then you take it out, chop it up, and combine it with garlic, ginger, green onions, red pepper, and in some cases, fish broth and salted shrimp. Then you throw it back into the pot and let it rot for 3-5 days.

Nearly a week later, you have the most delicious preserved vegetables available, which will keep you from starving to death during those long winter months, or worse yet, those 60-hour work weeks when you don't have time to go grocery shopping for fresh vegetables.