Place the beets in a large pot and cover with water. Bring to a gentle boil, then reduce heat and simmer until tender, about 20–25 minutes. Drain and let cool slightly. Slip off the skins by rubbing gently with your fingers or a paper towel.

Trim off the beet greens and roots. Slice the beets into ¼-inch rounds or wedges, then layer them evenly into sterilized canning jars.

In a saucepan, combine apple cider vinegar, water, sugar, salt, cinnamon stick, cloves, bay leaves, and peppercorns. Bring to a simmer over medium heat, stirring until sugar dissolves and spices infuse the liquid—about 5 minutes.

Carefully ladle the hot brine over the beets, leaving ½-inch headspace. Wipe rims clean, apply lids, and process in a boiling water bath for 10 minutes. Turn off heat, let jars sit in water for 5 minutes, then remove and cool on a towel—avoiding drafts.

Allow jars to rest undisturbed for at least 12 hours before tasting. The flavor deepens over the next few days—plan ahead for best results.