1. Trim beets to remove stems and root tips. Scrub clean. Bring beets to a boil in a pot full of water and cook 20-30 minutes until tender. Strain and allow to cool slightly so that you can peel and slice the beets. The peels should slide off easily with finger pressure, no knife needed. Slice or quarter, your choice.
2. Prepare pickling liquid by boiling water, vinegar, sugar and salt. If using, add cinnamon stick and simmer 5 minutes to infuse, then discard cinnamon stick.
3. Pack cooked beets and raw onion slices into wide mouth mason jars leaving 1/2 inch headspace. This recipe should fill 4 wide mouth pint jars. Add 2 whole cloves and 4 allspice berries to each jar.
4. Ladle hot brine over beets, onions and spices leaving 1/2 inch headspace. Apply lids and bands, and process in a water bath canner for 30 minutes, adjusting for altitude.