Wash and rinse the peppers. Pat dry with a paper towel. Trim the stems. With a toothpick, pole 5-7 holes into each pepper.
Place the peppers into a gallon-sized wide-mouthed jar. I wouldn't just throw them in, but carefully and efficiently fill the jar with the peppers.
In a medium-sized saucepan, bring to a simmer the soy sauce, water, and sugar over medium heat. Simmer until the sugar is all dissolved or for about 1 minute.
Take off the heat and add the vinegar. Pour the hot mixture into the jar full of peppers.
Make sure the peppers are submerged. Loosely secure the lid and let the peppers sit at room temperature away from sunlight for 2-3 days.
Drain the peppers into a large strainer and reserve the liquid. DO NOT THROW OUT THE SOY SAUCE MIXTURE. Pour only the liquid into a saucepan. Bring the soy sauce to a boil and then let cool.
Place the peppers back into the jar and then pour the cooled liquid back into the jar.
Secure the lid and refrigerate.