Prepare a boiling water bath and heat 3 pint-sized (473 ml) jars. Combine the vinegar, 2 cups (475 ml) of water, and salt in a large pot and bring to a boil over high heat, stirring to dissolve the salt. Reduce the heat, add the cauliflower and beets, and simmer for 5 minutes. Remove from the heat.
Add 2 garlic halves and ½ teaspoon peppercorns to each jar. Using a slotted spoon, pack the vegetables tightly into the jars, making sure to distribute the beets evenly. (There may be beets left over.) Ladle the hot brine over the vegetables leaving ½ inch (1 cm) of headspace. Bubble the jars well and remeasure the headspace, adding more brine if necessary. Wipe the rims with a damp cloth. Place the lids on the jars and screw on the rings just until you feel resistance. Process the jars in a boiling water bath for 10 minutes. Allow to cool in the water for 5 minutes before removing. Allow the cauliflower to cure for 1 week before opening. Store unopened jars in a cool, dark place for up to 1 year.
Note: I recommend using regular-mouth pint-sized (473 ml) jars for this project because the shoulders help keep the cauliflower submerged.
From The Joys of Jewish Preserving by Emily Paster, © 2017 Quarto Publishing Group. Used by permission from the publisher, Harvard Common Press, an imprint of Quarto Publishing Group. QuartoKnows.com