Arrange a rack in the center of the oven and preheat to 400ºF / 200ºC (if your oven runs hot, you may want to reduce the temperature by 15 to 25ºF / ~10ºC).
Remove any beet greens attached. Wash and scrub the beets, slice off the stalks and tails, then peel the beets (wear food-safe gloves to avoid staining hands).
For smaller beets, quarter them into 4 wedges. For medium beets, slice into 6 wedges. For large beets, slice into 8 wedges. The goal is for the beet wedges to be roughly the same size.
Transfer the beets to a parchment paper-lined sheet pan (parchment paper isn’t required but makes cleanup easy).
Toss with 1 ½ tablespoons olive oil, or enough oil to coat the beets well but not so much that they’re oily. Season with salt and pepper to taste: for Diamond Crystal kosher salt, I use ¾ tsp; for sea salt, scant ½ tsp; for table salt, heaping ¼ tsp.
Arrange on the lined pan with any cut sides facing down. Roast for 20 minutes then toss. Roast for another 15 minutes, or until tender and browned in spots (light charring is also okay). If your beets were large, they may need an extra 5-ish minutes.
Remove from the oven, allow to cool a bit. Season with a pinch of flaky sea salt, if desired, and/or other optional finishes.