Pack the carrots into a mason jar with the sliced garlic and peppercorns.
Whisk together the hot water, vinegar, salt and sugar until the salt and sugar are dissolved.
Cover the carrots in the water and vinegar mixture. Cover the jar and let rest for 30 minutes.
Enjoy or store in the refrigerator for up to 4 weeks.
Notes
If you are pickling the whole carrots, you will need 12 ounces and you will need a quart mason jar. If you are doing the slices you will need 8 ounces of carrots (by weight) and the 8 ounce (by liquid) sized mason jar.