Peel and dice radish into ½-inch cubes.
Pack radish cubes into a 32-ounce glass jar or container with an air-tight lid.
Stir together rice vinegar, sugar, salt, and ½ cup hot water until sugar and salt dissolve.
Pour vinegar brine over radish cubes. There should be enough brine to completely cover the radishes, but if it's shy by a few tablespoons, top off with plain water.
Keep Pickled Radish in refrigerator.
