Toss beets, oil, salt and pepper together in a large broiler-safe pot.
Arrange the beets in a single layer in the pot.
Combine water and vinegar in a measuring cup; pour over the beets.

Photography / Dera Burreson, Styling / Lauren McAnelly / Holly Rabikis
Cover the pot and place on the lower oven rack.
Bake, flipping the beets halfway through, until very tender, about 1 hour.
Remove from the oven and turn broiler to high.
Transfer the beets to a large rimmed baking sheet, arranging them in a single layer.
Sprinkle with oregano and serve.
- Daily Values (DVs) are the recommended amounts of nutrients to consume each day.
(-) Information is not currently available for this nutrient.