Prep the beets: Wash and peel the beets. Trim the ends so they’re flat for easier slicing.
Pat them completely dry to prevent steaming.
Slice thin and even: Use a mandoline set to 1/16–1/8 inch (about 1.5–3 mm). If using a knife, take your time and aim for uniform thickness. Even slices = even crisping.
Blot the slices: Spread beet rounds on a clean towel or paper towels and blot both sides. Removing surface moisture helps them crisp.
Season lightly: In a large bowl, toss beet slices with the oil until just coated.
Sprinkle on sea salt and any optional seasonings. Don’t over-oil; too much oil can cause sogginess.
Preheat the air fryer: Set to 300–320°F (150–160°C). Lower heat reduces burning and gives the slices time to dehydrate and crisp.
Arrange in a single layer: Place slices in the basket without overlapping.
Work in batches for best results.
Air fry and rotate: Cook for 12–18 minutes, shaking or flipping every 4–5 minutes. Watch closely in the final minutes. Some slices may finish earlier; remove those as they crisp and continue cooking the rest.
Cool to finish crisping: Transfer chips to a wire rack and let them cool for 5–10 minutes.
They firm up as they cool.
Taste and adjust: Add a pinch more sea salt, pepper, or a few drops of apple cider vinegar if you like a tangy edge.
Serve: Enjoy on their own, with hummus, or as a crunchy topper for salads and grain bowls.