Cut ends off beets (no need to peel if they are scrubbed). Using a mandolin or cheese plane, cut into thin slices. (Be careful of your fingers!).
Place beets into a bowl and toss with the olive oil and half the salt. Let sit while the oven preheats.
Preheat oven to 250 degrees F.
Place beet slices onto prepared baking sheets. Making sure they are not overlapping. Bake for about 40-50 minutes, until starting to get browned at edges and no longer soft, checking on them every now and then to make sure they don't burn. Let them cool on the baking sheet or a wire rack. Sprinkle with the rest of the sea salt and enjoy!
Notes
Short on time? You can try baking these at 400 degrees for 15 minutes. Again, just keeping a close eye out so they don't burn!