Preheat the oven to 400 degrees F and line a large baking sheet with parchment paper.
Slice your beets as thinly as possible. I used the slicer on my Veggie Bullet. If you do not have a slicing tool, you may slice by hand.
Add the sliced beets, oil, salt and rosemary to a mixing bowl and toss to combine. Then place on your prepared baking sheet in a single layer and bake for 15 minutes. Remove from the oven, and flip your chips and bake for 5 more minutes.