How to Make It
Trim beets, leaving root and 1-inch stem; scrub with a brush. Place in a medium saucepan with water to cover, and bring to a boil over high. Cover, reduce heat to medium, and simmer until tender, about 45 minutes. Drain and rinse with cold water; drain completely. Cool 5 minutes; trim roots, and rub off skins. Cut beets into 1/4-inch slices; place in a large bowl.
Stir together vinegar, water, sugar, onion, thyme, salt, oregano, and peppercorns in a medium saucepan, and bring to a boil over medium-high, stirring to dissolve sugar and salt. Pour hot liquid over beets; cover and chill at least 4 hours or up to overnight.