To save yourself time, use pre-roasted beets like Love Beets. If you are roasting your own beets, preheat the oven to 400 degrees F. Scrub and trim each beet. Use your fingers to rub a small amount of olive oil over each one before wrapping each in a piece of aluminum foil. Place the wrapped beets directly on the center oven rack. Roast small beets for ~40 minutes, and large beets for ~60 minutes.
To check if the beets are tender, use an oven mitt to remove one from the oven and open the foil to insert a fork into the beet. If it needs more time, put it back in the oven. If it's tender, remove all of the beets from the oven and open their foil packs. Let them cool enough for you to be able to touch them (slicing them in half helps). Remove their skins by gently rubbing your hands over them.
Add the roasted beets, peeled and roughly chopped cucumber, onion, tomato, and bell pepper to a large, high-powered blender. Pour in the water, and add the salt, pepper, vinegar, and olive oil. Blend until smooth, about 60 seconds. Taste seasonings and adjust as desired.
Chill in the fridge for at least 2 hours before serving. Taste and season with more salt and pepper as desired. Garnish with a dash of red wine vinegar and olive oil, and some fresh herbs and seeds.