Makes 4 pints
6 lb. small Chioggia or golden beets
2 cups white wine vinegar
2 cups sugar
6 cups thinly sliced red onion
1⁄4 cup pickling spice
12 whole cloves
4 pint canning jars and lids
Fill a canning kettle two-thirds full of water and bring to a boil. Wash, rinse, and sterilize the canning jars and lids.
Clean the beets and trim the stems to 1⁄2 in. Place beets in a saucepan, and cover with cold water. Bring to a boil, lower the heat, and simmer until tender, 15 to 20 min. Drain and hold in cold water. When cool, peel and cut off the stems.
Meanwhile, combine the vinegar and sugar in a non-reactive saucepan. Bring to a simmer over medium heat.
Toss the beets and onion slices together. Fill the jars with the mixture, pressing down so they are as full as possible. Put 1 tbsp. of the pickling spices and 3 cloves in each jar. Fill with simmering brine to 1⁄2 in. from the top. Wipe the rims clean and screw on the two-piece lids. Transfer jars to the boiling-water bath and process for 10 min. Cool, then label and store in a dark place for a month for flavors to develop.