Put all ingredients into your cooking vessel of choice. Stir. The peanuts will float, so plan to stir every so often as they cook.
For the stovetop: Bring the pot to a boil, turn to a steady simmer (medium low on my stove), cover, and cook for 2 ½ to 3 three hours, testing for doneness starting at about hour 2. This is the time to adjust seasoning if needed.
For a slow cooker: Cover and cook on low for 24 hours, stirring occasionally. (Yes. 24 hours.) Check for seasoning about 20 hours in, and adjust if necessary.
In either case, letting the peanuts cool in the cooking liquid will give you a more robust flavor.
To freeze: Allow the peanuts to cool in their liquid. Using a slotted spoon transfer the cooled boiled peanuts to a zipper freezer bag, force out any extra air, and seal. Freeze for up to six months.