jar funnel ($2 at mall kitchen stores and local "big box" stores, but it's usually cheaper online from our affiliates)
at least 1 large pot
large spoons and ladles
ball jars (Publix, Kroger, other grocery stores and some "big box" stores carry them - about $7 per dozen pint jars including the lids and rings)
1 water bath canner or a pressure canner (a large pressure pot with a lifting rack to sanitize the jars after filling about $75 to $200 at mall kitchen stores and "big box" stores, but it is cheaper online; see this page for more about pressure canners).
Selection. The most important step! you need beets that are fresh and crisp. Limp, old beets will make nasty tasting canned beets. Select firm, crisp beets. Remove and discard any soft, diseased, spotted and chewed up beets. How many beets and where to get them you can grow your own, pick your own, or buy them at the grocery store. About 7 pounds of 2- to 2½-inch diameter beets makes about 8 pints of pickled beets. I wouldn't use canned beets; what's the point: most of the flavor is gone from them, and you can always get fresh beets.
Wash the jars and lids this is a good time to get the jars ready! The dishwasher is fine for the jars; especially if it has a "sanitize" cycle. Otherwise put the jars in boiling water for 10 minutes.
I just put the lids in a small pot of almost boiling water for 5 minutes, and use the magnetic "lid lifter wand" (available from target, other big box stores, and often grocery stores; and available online - see this page) to pull them out.
Get the canner heating up rinse out your canner, put the rack in the bottom, and fill it with hot tap water (of course, follow the instruction that came with the canner, if they are different).
Put it on the stove over low heat just to get it heating up for later on.
Trim the ends and cut into smaller pieces: Just take a sharp knife and trim off beet tops, leaving an inch of stem and roots to prevent bleeding of color.
Wash the beets! I'm sure you can figure out how to scrub the beets in plain cold or lukewarm water using your hands or a vegetable brush.
Put similar sized beets (hopefully, they're all of a similar size so they take the same time to cook) together with enough boiling water to cover them and cook until tender (usually about 30 to 45 minutes in an open pot, or 10 - 15 minutes in a pressure cooker).
Drain and discard the liquid (it would weaken the pickling solution).
Cool the beets: You can pour ice over them, or just let them cool on their own. It's just to cool them enough so you can handle them to remove the skins, stems, roots and then slice or quarter them.
Trim off the roots and stems. The skins should easily slide off.
Slice the beets into ¼-inch slices. You can leave the beets whole (if they are small, say 1 inch or less), or quarter them or slice them into ¼-inch slices. This is to help more fit in the jars and to help the seasoning to penetrate them better.
(Optional) Slice the onions: If you like onions in the mix (most people do), peel and thinly slice the onions.
Combine the vinegar, salt, sugar (or splenda if you need a no-sugar version) and fresh water in a large pot.
Put the spices in cheesecloth bag and add to vinegar mixture.
Bring to a boil.
Heat the mixture with the beets and onions.
Add beets and onions to the pot and simmer for 5 minutes.
Then remove the spice bag.
Packing the beets in the canning jars. This is called "hot packing"! Fill the jars with beets and onions, leaving ½-inch headspace. Pack the jars fairly tightly, but be sure to leave ½-inch of space at the TOP of the jar. That is called "headspace" and is needed for expansion during heating in the water bath.
Pour boiling cooking liquid into each packed jar. Use a ladle or pyrex measuring cup to carefully fill each packed jar with the hot vinegar solution, again allowing ½-inch headspace. The beets should be covered and there should still be ½ inch of airspace left in the top of each jar. Be careful not to burn yourself, (or anyone else - children should be kept back during this step!).
Put the lids on each jar and seal them by putting a ring on and screwing it down snugly (but not with all your might, just "snug").
Using the jar tongs, put the jars on the rack in the canner.
Make sure the tops of the jars are covered by at least 1 inch of water.